diff --git a/.travis.yml b/.travis.yml
index c35d29201..233117718 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -19,7 +19,6 @@ after_script:
  - if [ "${TRAVIS_OS_NAME}" = "linux" ]; then ./openmw_test_suite; fi
 notifications:
   recipients:
-    - lgromanowski+travis.ci@gmail.com
     - corrmage+travis-ci@gmail.com
   email:
     on_success: change
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 37faeefb2..4d5c68cde 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -13,7 +13,7 @@ message(STATUS "Configuring OpenMW...")
 
 set(OPENMW_VERSION_MAJOR 0)
 set(OPENMW_VERSION_MINOR 33)
-set(OPENMW_VERSION_RELEASE 0)
+set(OPENMW_VERSION_RELEASE 1)
 
 set(OPENMW_VERSION_COMMITHASH "")
 set(OPENMW_VERSION_TAGHASH "")
diff --git a/apps/opencs/view/render/mousestate.cpp b/apps/opencs/view/render/mousestate.cpp
index af835d0a5..45e846f74 100644
--- a/apps/opencs/view/render/mousestate.cpp
+++ b/apps/opencs/view/render/mousestate.cpp
@@ -255,7 +255,7 @@ namespace CSVRender
                 std::pair<std::string, Ogre::Vector3> result = terrainUnderCursor(event->x(), event->y());
                 if(result.first != "")
                 {
-                    // FIXME: terrain editing
+                    // FIXME: terrain editing goes here
                 }
                 break;
             }
@@ -267,6 +267,8 @@ namespace CSVRender
     void MouseState::mouseDoubleClickEvent (QMouseEvent *event)
     {
         event->ignore();
+        //mPhysics->toggleDebugRendering(mSceneManager);
+        //mParent->flagAsModified();
     }
 
     bool MouseState::wheelEvent (QWheelEvent *event)
diff --git a/apps/opencs/view/world/physicsmanager.cpp b/apps/opencs/view/world/physicsmanager.cpp
index f8e022e5d..fa8db9e1e 100644
--- a/apps/opencs/view/world/physicsmanager.cpp
+++ b/apps/opencs/view/world/physicsmanager.cpp
@@ -2,6 +2,8 @@
 
 #include <iostream>
 
+#include <openengine/bullet/BulletShapeLoader.h>
+
 #include "../render/worldspacewidget.hpp"
 #include "physicssystem.hpp"
 
@@ -54,6 +56,12 @@ namespace CSVWorld
         {
             mSceneWidgets.erase(it);
         }
+
+        // cleanup global resources used by OEngine
+        if(mPhysics.empty())
+        {
+            delete OEngine::Physic::BulletShapeManager::getSingletonPtr();
+        }
     }
 
     // called from CSVRender::WorldspaceWidget() to get widgets' association with Document&
@@ -74,6 +82,9 @@ namespace CSVWorld
         throw std::runtime_error("No physics system found for the given document.");
     }
 
+    // deprecated by removeDocument() and may be deleted in future code updates
+    // however there may be some value in removing the deleted scene widgets from the
+    // list so that the list does not grow forever
     void PhysicsManager::removeSceneWidget(CSVRender::WorldspaceWidget *widget)
     {
         CSVRender::SceneWidget *sceneWidget = static_cast<CSVRender::SceneWidget *>(widget);
diff --git a/apps/opencs/view/world/physicssystem.cpp b/apps/opencs/view/world/physicssystem.cpp
index 73063b6be..57909f4d3 100644
--- a/apps/opencs/view/world/physicssystem.cpp
+++ b/apps/opencs/view/world/physicssystem.cpp
@@ -22,10 +22,7 @@ namespace CSVWorld
 
     PhysicsSystem::~PhysicsSystem()
     {
-        // FIXME: OEngine does not behave well when multiple instances are created
-        // and deleted, sometimes resulting in crashes.  Skip the deletion until the physics
-        // code is moved out of OEngine.
-        //delete mEngine;
+        delete mEngine;
     }
 
     // looks up the scene manager based on the scene node name (inefficient)
@@ -278,6 +275,8 @@ namespace CSVWorld
     void PhysicsSystem::addSceneManager(Ogre::SceneManager *sceneMgr, CSVRender::SceneWidget *sceneWidget)
     {
         mSceneWidgets[sceneMgr] = sceneWidget;
+
+        mEngine->createDebugDraw(sceneMgr);
     }
 
     std::map<Ogre::SceneManager*, CSVRender::SceneWidget *> PhysicsSystem::sceneWidgets()
@@ -287,6 +286,8 @@ namespace CSVWorld
 
     void PhysicsSystem::removeSceneManager(Ogre::SceneManager *sceneMgr)
     {
+        mEngine->removeDebugDraw(sceneMgr);
+
         mSceneWidgets.erase(sceneMgr);
     }
 
@@ -310,8 +311,6 @@ namespace CSVWorld
         if(!sceneMgr)
             return;
 
-        mEngine->setSceneManager(sceneMgr);
-
         CSMSettings::UserSettings &userSettings = CSMSettings::UserSettings::instance();
         if(!(userSettings.setting("debug/mouse-picking", QString("false")) == "true" ? true : false))
         {
@@ -319,7 +318,7 @@ namespace CSVWorld
             return;
         }
 
-        mEngine->toggleDebugRendering();
-        mEngine->stepSimulation(0.0167); // DebugDrawer::step() not directly accessible
+        mEngine->toggleDebugRendering(sceneMgr);
+        mEngine->stepDebug(sceneMgr);
     }
 }
diff --git a/apps/openmw/mwmechanics/actors.cpp b/apps/openmw/mwmechanics/actors.cpp
index 02594258d..2e835d57e 100644
--- a/apps/openmw/mwmechanics/actors.cpp
+++ b/apps/openmw/mwmechanics/actors.cpp
@@ -369,7 +369,7 @@ namespace MWMechanics
     void Actors::updateNpc (const MWWorld::Ptr& ptr, float duration)
     {
         updateDrowning(ptr, duration);
-        calculateNpcStatModifiers(ptr);
+        calculateNpcStatModifiers(ptr, duration);
         updateEquippedLight(ptr, duration);
     }
 
@@ -499,6 +499,9 @@ namespace MWMechanics
                              effects.get(EffectKey(ESM::MagicEffect::DrainAttribute, i)).getMagnitude() -
                              effects.get(EffectKey(ESM::MagicEffect::AbsorbAttribute, i)).getMagnitude());
 
+            stat.damage(effects.get(EffectKey(ESM::MagicEffect::DamageAttribute, i)).getMagnitude() * duration * 1.5);
+            stat.restore(effects.get(EffectKey(ESM::MagicEffect::RestoreAttribute, i)).getMagnitude() * duration * 1.5);
+
             creatureStats.setAttribute(i, stat);
         }
 
@@ -855,7 +858,7 @@ namespace MWMechanics
         }
     }
 
-    void Actors::calculateNpcStatModifiers (const MWWorld::Ptr& ptr)
+    void Actors::calculateNpcStatModifiers (const MWWorld::Ptr& ptr, float duration)
     {
         NpcStats &npcStats = ptr.getClass().getNpcStats(ptr);
         const MagicEffects &effects = npcStats.getMagicEffects();
@@ -867,6 +870,9 @@ namespace MWMechanics
             skill.setModifier(effects.get(EffectKey(ESM::MagicEffect::FortifySkill, i)).getMagnitude() -
                              effects.get(EffectKey(ESM::MagicEffect::DrainSkill, i)).getMagnitude() -
                              effects.get(EffectKey(ESM::MagicEffect::AbsorbSkill, i)).getMagnitude());
+
+            skill.damage(effects.get(EffectKey(ESM::MagicEffect::DamageSkill, i)).getMagnitude() * duration * 1.5);
+            skill.restore(effects.get(EffectKey(ESM::MagicEffect::RestoreSkill, i)).getMagnitude() * duration * 1.5);
         }
     }
 
@@ -1534,6 +1540,6 @@ namespace MWMechanics
         adjustMagicEffects(ptr);
         calculateCreatureStatModifiers(ptr, 0.f);
         if (ptr.getClass().isNpc())
-            calculateNpcStatModifiers(ptr);
+            calculateNpcStatModifiers(ptr, 0.f);
     }
 }
diff --git a/apps/openmw/mwmechanics/actors.hpp b/apps/openmw/mwmechanics/actors.hpp
index 55f1719f6..0ccfaad78 100644
--- a/apps/openmw/mwmechanics/actors.hpp
+++ b/apps/openmw/mwmechanics/actors.hpp
@@ -34,7 +34,7 @@ namespace MWMechanics
             void calculateDynamicStats (const MWWorld::Ptr& ptr);
 
             void calculateCreatureStatModifiers (const MWWorld::Ptr& ptr, float duration);
-            void calculateNpcStatModifiers (const MWWorld::Ptr& ptr);
+            void calculateNpcStatModifiers (const MWWorld::Ptr& ptr, float duration);
 
             void calculateRestoration (const MWWorld::Ptr& ptr, float duration);
 
diff --git a/apps/openmw/mwmechanics/spells.cpp b/apps/openmw/mwmechanics/spells.cpp
index 681f01f04..a1b73bc47 100644
--- a/apps/openmw/mwmechanics/spells.cpp
+++ b/apps/openmw/mwmechanics/spells.cpp
@@ -70,11 +70,13 @@ namespace MWMechanics
             if (mPermanentSpellEffects.find(lower) != mPermanentSpellEffects.end())
             {
                 MagicEffects & effects = mPermanentSpellEffects[lower];
-                for (MagicEffects::Collection::const_iterator effectIt = effects.begin(); effectIt != effects.end(); ++effectIt)
+                for (MagicEffects::Collection::const_iterator effectIt = effects.begin(); effectIt != effects.end();)
                 {
                     const ESM::MagicEffect * magicEffect = MWBase::Environment::get().getWorld()->getStore().get<ESM::MagicEffect>().find(effectIt->first.mId);
                     if (magicEffect->mData.mFlags & ESM::MagicEffect::Harmful)
-                        effects.remove(effectIt->first);
+                        effects.remove((effectIt++)->first);
+                    else
+                        ++effectIt;
                 }
             }
             mCorprusSpells.erase(corprusIt);
diff --git a/apps/openmw/mwmechanics/stat.hpp b/apps/openmw/mwmechanics/stat.hpp
index 0fb4c5732..1c33db0fd 100644
--- a/apps/openmw/mwmechanics/stat.hpp
+++ b/apps/openmw/mwmechanics/stat.hpp
@@ -236,20 +236,20 @@ namespace MWMechanics
     {
         int mBase;
         int mModifier;
-        int mDamage;
+        float mDamage; // needs to be float to allow continuous damage
 
     public:
         AttributeValue() : mBase(0), mModifier(0), mDamage(0) {}
 
-        int getModified() const { return std::max(0, mBase - mDamage + mModifier); }
+        int getModified() const { return std::max(0, mBase - (int) mDamage + mModifier); }
         int getBase() const { return mBase; }
         int getModifier() const {  return mModifier; }
 
         void setBase(int base) { mBase = std::max(0, base); }
         void setModifier(int mod) { mModifier = mod; }
 
-        void damage(int damage) { mDamage += damage; }
-        void restore(int amount) { mDamage -= std::min(mDamage, amount); }
+        void damage(float damage) { mDamage += damage; }
+        void restore(float amount) { mDamage -= std::min(mDamage, amount); }
         int getDamage() const { return mDamage; }
 
         void writeState (ESM::StatState<int>& state) const;
diff --git a/apps/openmw/mwscript/dialogueextensions.cpp b/apps/openmw/mwscript/dialogueextensions.cpp
index a88c5a101..563a9dde3 100644
--- a/apps/openmw/mwscript/dialogueextensions.cpp
+++ b/apps/openmw/mwscript/dialogueextensions.cpp
@@ -125,6 +125,9 @@ namespace MWScript
                 {
                     MWWorld::Ptr ptr = R()(runtime);
 
+                    if (!ptr.getRefData().isEnabled())
+                        return;
+
                     MWBase::Environment::get().getDialogueManager()->startDialogue (ptr);
                 }
         };
diff --git a/apps/openmw/mwworld/physicssystem.cpp b/apps/openmw/mwworld/physicssystem.cpp
index aba120baa..eecc4a02d 100644
--- a/apps/openmw/mwworld/physicssystem.cpp
+++ b/apps/openmw/mwworld/physicssystem.cpp
@@ -14,6 +14,7 @@
 #include <openengine/bullet/physic.hpp>
 #include <openengine/bullet/BtOgreExtras.h>
 #include <openengine/ogre/renderer.hpp>
+#include <openengine/bullet/BulletShapeLoader.h>
 
 #include <components/nifbullet/bulletnifloader.hpp>
 
@@ -471,10 +472,9 @@ namespace MWWorld
                 physicActor->setInertialForce(Ogre::Vector3(0.0f));
             else
             {
-                float diff = time*-627.2f;
+                inertia.z += time * -627.2f;
                 if (inertia.z < 0)
-                    diff *= slowFall;
-                inertia.z += diff;
+                    inertia.z *= slowFall;
                 physicActor->setInertialForce(inertia);
             }
             physicActor->setOnGround(isOnGround);
@@ -498,6 +498,7 @@ namespace MWWorld
         if (mWaterCollisionObject.get())
             mEngine->mDynamicsWorld->removeCollisionObject(mWaterCollisionObject.get());
         delete mEngine;
+        delete OEngine::Physic::BulletShapeManager::getSingletonPtr();
     }
 
     OEngine::Physic::PhysicEngine* PhysicsSystem::getEngine()
@@ -863,8 +864,8 @@ namespace MWWorld
                     continue;
                 physicActor->setCanWaterWalk(waterCollision);
 
-                // 100 points of slowfall reduce gravity by 90% (this is just a guess)
-                float slowFall = 1-std::min(std::max(0.f, (effects.get(ESM::MagicEffect::SlowFall).getMagnitude() / 100.f) * 0.9f), 0.9f);
+                // Slow fall reduces fall speed by a factor of (effect magnitude / 200)
+                float slowFall = 1.f - std::max(0.f, std::min(1.f, effects.get(ESM::MagicEffect::SlowFall).getMagnitude() * 0.005f));
 
                 Ogre::Vector3 newpos = MovementSolver::move(iter->first, iter->second, mTimeAccum,
                                                             world->isFlying(iter->first),
diff --git a/components/esm/statstate.hpp b/components/esm/statstate.hpp
index f1a3b4d79..801d0ce82 100644
--- a/components/esm/statstate.hpp
+++ b/components/esm/statstate.hpp
@@ -15,7 +15,7 @@ namespace ESM
         T mMod; // Note: can either be the modifier, or the modified value.
                 // A bit inconsistent, but we can't fix this without breaking compatibility.
         T mCurrent;
-        T mDamage;
+        float mDamage;
         float mProgress;
 
         StatState();
@@ -36,8 +36,14 @@ namespace ESM
         esm.getHNOT (mMod, "STMO");
         mCurrent = 0;
         esm.getHNOT (mCurrent, "STCU");
-        mDamage = 0;
-        esm.getHNOT (mDamage, "STDA");
+
+        // mDamage was changed to a float; ensure backwards compatibility
+        T oldDamage = 0;
+        esm.getHNOT(oldDamage, "STDA");
+        mDamage = oldDamage;
+
+        esm.getHNOT (mDamage, "STDF");
+
         mProgress = 0;
         esm.getHNOT (mProgress, "STPR");
     }
@@ -54,7 +60,7 @@ namespace ESM
             esm.writeHNT ("STCU", mCurrent);
 
         if (mDamage)
-            esm.writeHNT ("STDA", mDamage);
+            esm.writeHNT ("STDF", mDamage);
 
         if (mProgress)
             esm.writeHNT ("STPR", mProgress);
diff --git a/credits.txt b/credits.txt
index 10065b44d..d7fe230c7 100644
--- a/credits.txt
+++ b/credits.txt
@@ -46,6 +46,7 @@ Jannik Heller (scrawl)
 Jason Hooks (jhooks)
 jeaye
 Jeffrey Haines (Jyby)
+Jengerer
 Joel Graff (graffy)
 John Blomberg (fstp)
 Jordan Ayers
diff --git a/files/openmw.cfg b/files/openmw.cfg
index e105b6304..b60c1ba72 100644
--- a/files/openmw.cfg
+++ b/files/openmw.cfg
@@ -1,5 +1,5 @@
-data="?global?data"
 data="?mw?Data Files"
+data=${MORROWIND_DATA_FILES}
 data-local="?userdata?data"
 resources=${OPENMW_RESOURCE_FILES}
 script-blacklist=Museum
diff --git a/libs/openengine/bullet/BtOgreExtras.h b/libs/openengine/bullet/BtOgreExtras.h
index 9572b8a7b..f8c1fe41d 100644
--- a/libs/openengine/bullet/BtOgreExtras.h
+++ b/libs/openengine/bullet/BtOgreExtras.h
@@ -212,8 +212,10 @@ public:
 
     ~DebugDrawer()
     {
-                Ogre::MaterialManager::getSingleton().remove("BtOgre/DebugLines");
-                Ogre::ResourceGroupManager::getSingleton().destroyResourceGroup("BtOgre");
+        if (Ogre::MaterialManager::getSingleton().resourceExists("BtOgre/DebugLines"))
+            Ogre::MaterialManager::getSingleton().remove("BtOgre/DebugLines");
+        if (Ogre::ResourceGroupManager::getSingleton().resourceGroupExists("BtOgre"))
+            Ogre::ResourceGroupManager::getSingleton().destroyResourceGroup("BtOgre");
         delete mLineDrawer;
     }
 
diff --git a/libs/openengine/bullet/physic.cpp b/libs/openengine/bullet/physic.cpp
index 0c61253bf..d7db81595 100644
--- a/libs/openengine/bullet/physic.cpp
+++ b/libs/openengine/bullet/physic.cpp
@@ -114,7 +114,7 @@ namespace Physic
         {
             mEngine->mDynamicsWorld->removeRigidBody(mBody);
             delete mBody;
-        }  
+        }
     }
 
     void PhysicActor::enableCollisionMode(bool collision)
@@ -356,7 +356,8 @@ namespace Physic
         delete broadphase;
         delete mShapeLoader;
 
-        delete BulletShapeManager::getSingletonPtr();
+        // Moved the cleanup to mwworld/physicssystem
+        //delete BulletShapeManager::getSingletonPtr();
     }
 
     void PhysicEngine::addHeightField(float* heights,
@@ -863,5 +864,76 @@ namespace Physic
         }
     }
 
+    int PhysicEngine::toggleDebugRendering(Ogre::SceneManager *sceneMgr)
+    {
+        if(!sceneMgr)
+            return 0;
+
+        std::map<Ogre::SceneManager *, BtOgre::DebugDrawer *>::iterator iter =
+            mDebugDrawers.find(sceneMgr);
+        if(iter != mDebugDrawers.end()) // found scene manager
+        {
+            if((*iter).second)
+            {
+                // set a new drawer each time (maybe with a different scene manager)
+                mDynamicsWorld->setDebugDrawer(mDebugDrawers[sceneMgr]);
+                if(!mDebugDrawers[sceneMgr]->getDebugMode())
+                    mDebugDrawers[sceneMgr]->setDebugMode(1 /*mDebugDrawFlags*/);
+                else
+                    mDebugDrawers[sceneMgr]->setDebugMode(0);
+                mDynamicsWorld->debugDrawWorld();
+
+                return mDebugDrawers[sceneMgr]->getDebugMode();
+            }
+        }
+        return 0;
+    }
+
+    void PhysicEngine::stepDebug(Ogre::SceneManager *sceneMgr)
+    {
+        if(!sceneMgr)
+            return;
+
+        std::map<Ogre::SceneManager *, BtOgre::DebugDrawer *>::iterator iter =
+            mDebugDrawers.find(sceneMgr);
+        if(iter != mDebugDrawers.end()) // found scene manager
+        {
+            if((*iter).second)
+                (*iter).second->step();
+            else
+                return;
+        }
+    }
+
+    void PhysicEngine::createDebugDraw(Ogre::SceneManager *sceneMgr)
+    {
+        if(mDebugDrawers.find(sceneMgr) == mDebugDrawers.end())
+        {
+            mDebugSceneNodes[sceneMgr] = sceneMgr->getRootSceneNode()->createChildSceneNode();
+            mDebugDrawers[sceneMgr] = new BtOgre::DebugDrawer(mDebugSceneNodes[sceneMgr], mDynamicsWorld);
+            mDebugDrawers[sceneMgr]->setDebugMode(0);
+        }
+    }
+
+    void PhysicEngine::removeDebugDraw(Ogre::SceneManager *sceneMgr)
+    {
+        std::map<Ogre::SceneManager *, BtOgre::DebugDrawer *>::iterator iter =
+            mDebugDrawers.find(sceneMgr);
+        if(iter != mDebugDrawers.end())
+        {
+            delete (*iter).second;
+            mDebugDrawers.erase(iter);
+        }
+
+        std::map<Ogre::SceneManager *, Ogre::SceneNode *>::iterator it =
+            mDebugSceneNodes.find(sceneMgr);
+        if(it != mDebugSceneNodes.end())
+        {
+            std::string sceneNodeName = (*it).second->getName();
+            if(sceneMgr->hasSceneNode(sceneNodeName))
+                sceneMgr->destroySceneNode(sceneNodeName);
+        }
+    }
+
 }
 }
diff --git a/libs/openengine/bullet/physic.hpp b/libs/openengine/bullet/physic.hpp
index a77b60ab6..fb6ae0ceb 100644
--- a/libs/openengine/bullet/physic.hpp
+++ b/libs/openengine/bullet/physic.hpp
@@ -348,6 +348,15 @@ namespace Physic
         bool isDebugCreated;
         bool mDebugActive;
 
+        // for OpenCS with multiple engines per document
+        std::map<Ogre::SceneManager *, BtOgre::DebugDrawer *> mDebugDrawers;
+        std::map<Ogre::SceneManager *, Ogre::SceneNode *> mDebugSceneNodes;
+
+        int toggleDebugRendering(Ogre::SceneManager *sceneMgr);
+        void stepDebug(Ogre::SceneManager *sceneMgr);
+        void createDebugDraw(Ogre::SceneManager *sceneMgr);
+        void removeDebugDraw(Ogre::SceneManager *sceneMgr);
+
     private:
         PhysicEngine(const PhysicEngine&);
         PhysicEngine& operator=(const PhysicEngine&);
diff --git a/readme.txt b/readme.txt
index cb533e9fb..810a0e055 100644
--- a/readme.txt
+++ b/readme.txt
@@ -3,7 +3,7 @@ OpenMW: A reimplementation of The Elder Scrolls III: Morrowind
 OpenMW is an attempt at recreating the engine for the popular role-playing game
 Morrowind by Bethesda Softworks. You need to own and install the original game for OpenMW to work.
 
-Version: 0.33.0
+Version: 0.33.1
 License: GPL (see GPL3.txt for more information)
 Website: http://www.openmw.org
 
@@ -98,6 +98,10 @@ Allowed options:
 
 CHANGELOG
 
+0.33.1
+
+Bug #2108: OpenCS fails to build
+
 0.33.0
 
 Bug #371: If console assigned to ` (probably to any symbolic key), "`" symbol will be added to console every time it closed