diff --git a/apps/openmw/mwrender/animation.cpp b/apps/openmw/mwrender/animation.cpp
index 4b0eec7b9..f6df24358 100644
--- a/apps/openmw/mwrender/animation.cpp
+++ b/apps/openmw/mwrender/animation.cpp
@@ -1436,7 +1436,7 @@ namespace MWRender
                 return sceneMgr->createInstance(found->second);
         }
         else
-            return sceneMgr->createInstance(model);
+            return sceneMgr->getInstance(model);
     }
 
     void Animation::setObjectRoot(const std::string &model, bool forceskeleton, bool baseonly, bool isCreature)
diff --git a/apps/openmw/mwworld/worldimp.cpp b/apps/openmw/mwworld/worldimp.cpp
index e3658285d..502ff8843 100644
--- a/apps/openmw/mwworld/worldimp.cpp
+++ b/apps/openmw/mwworld/worldimp.cpp
@@ -409,7 +409,8 @@ namespace MWWorld
                 if (getPlayerPtr().isInCell())
                 {
                     mWorldScene->preloadCell(getPlayerPtr().getCell(), true);
-                    mWorldScene->preloadTerrain(getPlayerPtr().getRefData().getPosition().asVec3());
+                    if (getPlayerPtr().getCell()->isExterior())
+                        mWorldScene->preloadTerrain(getPlayerPtr().getRefData().getPosition().asVec3());
                 }
                 break;
             default:
diff --git a/components/nifosg/nifloader.cpp b/components/nifosg/nifloader.cpp
index eef678b36..a1aa74cab 100644
--- a/components/nifosg/nifloader.cpp
+++ b/components/nifosg/nifloader.cpp
@@ -244,10 +244,8 @@ namespace NifOsg
                 osg::ref_ptr<NifOsg::KeyframeController> callback(new NifOsg::KeyframeController(key->data.getPtr()));
                 callback->setFunction(std::shared_ptr<NifOsg::ControllerFunction>(new NifOsg::ControllerFunction(key)));
 
-                if (target.mKeyframeControllers.find(strdata->string) != target.mKeyframeControllers.end())
+                if (!target.mKeyframeControllers.emplace(strdata->string, callback).second)
                     Log(Debug::Verbose) << "Controller " << strdata->string << " present more than once in " << nif->getFilename() << ", ignoring later version";
-                else
-                    target.mKeyframeControllers[strdata->string] = callback;
             }
         }
 
diff --git a/components/resource/objectcache.cpp b/components/resource/objectcache.cpp
index e8c082f91..ffe150c74 100644
--- a/components/resource/objectcache.cpp
+++ b/components/resource/objectcache.cpp
@@ -75,10 +75,11 @@ void ObjectCache::updateTimeStampOfObjectsInCacheWithExternalReferences(double r
         itr!=_objectCache.end();
         ++itr)
     {
-        // if ref count is greater the 1 the object has an external reference.
-        if (itr->second.first->referenceCount()>1)
+        // If ref count is greater than 1, the object has an external reference.
+        // If the timestamp is yet to be initialized, it needs to be updated too.
+        if (itr->second.first->referenceCount()>1 || itr->second.second == 0.0)
         {
-            // so update it time stamp.
+            // So update it.
             itr->second.second = referenceTime;
         }
     }
diff --git a/components/resource/scenemanager.cpp b/components/resource/scenemanager.cpp
index 328a10cd1..d360e92b1 100644
--- a/components/resource/scenemanager.cpp
+++ b/components/resource/scenemanager.cpp
@@ -729,6 +729,7 @@ namespace Resource
 
     void SceneManager::reportStats(unsigned int frameNumber, osg::Stats *stats) const
     {
+        if (mIncrementalCompileOperation)
         {
             OpenThreads::ScopedLock<OpenThreads::Mutex> lock(*mIncrementalCompileOperation->getToCompiledMutex());
             stats->setAttribute(frameNumber, "Compiling", mIncrementalCompileOperation->getToCompile().size());
diff --git a/components/sceneutil/lightmanager.cpp b/components/sceneutil/lightmanager.cpp
index cb6a12c87..f0fd0ef9f 100644
--- a/components/sceneutil/lightmanager.cpp
+++ b/components/sceneutil/lightmanager.cpp
@@ -234,6 +234,7 @@ namespace SceneUtil
         {
             osg::ref_ptr<osg::StateSet> stateset = new osg::StateSet;
             std::vector<osg::ref_ptr<osg::Light> > lights;
+            lights.reserve(lightList.size());
             for (unsigned int i=0; i<lightList.size();++i)
             {
                 lights.push_back(lightList[i]->mLightSource->getLight(frameNum));
diff --git a/components/sceneutil/visitor.cpp b/components/sceneutil/visitor.cpp
index 3c3559a08..876ea920f 100644
--- a/components/sceneutil/visitor.cpp
+++ b/components/sceneutil/visitor.cpp
@@ -61,10 +61,7 @@ namespace SceneUtil
     {
         // Take transformation for first found node in file
         const std::string nodeName = Misc::StringUtils::lowerCase(trans.getName());
-        if (mMap.find(nodeName) == mMap.end())
-        {
-            mMap[nodeName] = &trans;
-        }
+        mMap.emplace(nodeName, &trans);
 
         traverse(trans);
     }
diff --git a/components/terrain/cellborder.cpp b/components/terrain/cellborder.cpp
index d9e6d52fc..64434727e 100644
--- a/components/terrain/cellborder.cpp
+++ b/components/terrain/cellborder.cpp
@@ -7,7 +7,7 @@
 #include "world.hpp"
 #include "../esm/loadland.hpp"
 
-namespace MWRender
+namespace Terrain
 {
 
 CellBorder::CellBorder(Terrain::World *world, osg::Group *root, int borderMask):
diff --git a/components/terrain/cellborder.hpp b/components/terrain/cellborder.hpp
index 530ea31ca..908cdea09 100644
--- a/components/terrain/cellborder.hpp
+++ b/components/terrain/cellborder.hpp
@@ -7,10 +7,7 @@
 namespace Terrain
 {
     class World;
-}
 
-namespace MWRender
-{
     /**
      * @Brief Handles the debug cell borders.
      */
diff --git a/components/terrain/compositemaprenderer.cpp b/components/terrain/compositemaprenderer.cpp
index 3dc0aa41c..0ef649197 100644
--- a/components/terrain/compositemaprenderer.cpp
+++ b/components/terrain/compositemaprenderer.cpp
@@ -122,6 +122,8 @@ void CompositeMapRenderer::compile(CompositeMap &compositeMap, osg::RenderInfo &
 
         ++compositeMap.mCompiled;
 
+        compositeMap.mDrawables[i] = nullptr;
+
         if (timeLeft)
         {
             *timeLeft -= timer.time_s();
@@ -131,6 +133,8 @@ void CompositeMapRenderer::compile(CompositeMap &compositeMap, osg::RenderInfo &
                 break;
         }
     }
+    if (compositeMap.mCompiled == compositeMap.mDrawables.size())
+        compositeMap.mDrawables = std::vector<osg::ref_ptr<osg::Drawable>>();
 
     state.haveAppliedAttribute(osg::StateAttribute::VIEWPORT);
 
diff --git a/components/terrain/quadtreeworld.cpp b/components/terrain/quadtreeworld.cpp
index 6ec89721a..594b2b755 100644
--- a/components/terrain/quadtreeworld.cpp
+++ b/components/terrain/quadtreeworld.cpp
@@ -163,25 +163,29 @@ public:
                 boundingBox.expandBy(child->getBoundingBox());
         }
 
-        parent->setBoundingBox(boundingBox);
+        if (!boundingBox.valid())
+            parent->removeChildren(0, 4);
+        else
+            parent->setBoundingBox(boundingBox);
     }
 
     QuadTreeNode* addChild(QuadTreeNode* parent, ChildDirection direction, float size)
     {
+        float halfSize = size/2.f;
         osg::Vec2f center;
         switch (direction)
         {
         case SW:
-            center = parent->getCenter() + osg::Vec2f(-size/2.f,-size/2.f);
+            center = parent->getCenter() + osg::Vec2f(-halfSize,-halfSize);
             break;
         case SE:
-            center = parent->getCenter() + osg::Vec2f(size/2.f, -size/2.f);
+            center = parent->getCenter() + osg::Vec2f(halfSize, -halfSize);
             break;
         case NW:
-            center = parent->getCenter() + osg::Vec2f(-size/2.f, size/2.f);
+            center = parent->getCenter() + osg::Vec2f(-halfSize, halfSize);
             break;
         case NE:
-            center = parent->getCenter() + osg::Vec2f(size/2.f, size/2.f);
+            center = parent->getCenter() + osg::Vec2f(halfSize, halfSize);
             break;
         default:
             break;
@@ -203,8 +207,8 @@ public:
         mStorage->getMinMaxHeights(size, center, minZ, maxZ);
 
         float cellWorldSize = mStorage->getCellWorldSize();
-        osg::BoundingBox boundingBox(osg::Vec3f((center.x()-size)*cellWorldSize, (center.y()-size)*cellWorldSize, minZ),
-                                osg::Vec3f((center.x()+size)*cellWorldSize, (center.y()+size)*cellWorldSize, maxZ));
+        osg::BoundingBox boundingBox(osg::Vec3f((center.x()-halfSize)*cellWorldSize, (center.y()-halfSize)*cellWorldSize, minZ),
+                                osg::Vec3f((center.x()+halfSize)*cellWorldSize, (center.y()+halfSize)*cellWorldSize, maxZ));
         node->setBoundingBox(boundingBox);
 
         return node;
diff --git a/components/terrain/terraingrid.cpp b/components/terrain/terraingrid.cpp
index dbc1429da..1888a02b3 100644
--- a/components/terrain/terraingrid.cpp
+++ b/components/terrain/terraingrid.cpp
@@ -84,7 +84,7 @@ void TerrainGrid::loadCell(int x, int y)
 
 void TerrainGrid::unloadCell(int x, int y)
 {
-    MWRender::CellBorder::CellGrid::iterator it = mGrid.find(std::make_pair(x,y));
+    CellBorder::CellGrid::iterator it = mGrid.find(std::make_pair(x,y));
     if (it == mGrid.end())
         return;
 
diff --git a/components/terrain/terraingrid.hpp b/components/terrain/terraingrid.hpp
index 87e3b432c..eb30fb97d 100644
--- a/components/terrain/terraingrid.hpp
+++ b/components/terrain/terraingrid.hpp
@@ -33,7 +33,7 @@ namespace Terrain
         // split each ESM::Cell into mNumSplits*mNumSplits terrain chunks
         unsigned int mNumSplits;
 
-        MWRender::CellBorder::CellGrid mGrid;
+        CellBorder::CellGrid mGrid;
     };
 }
 
diff --git a/components/terrain/world.cpp b/components/terrain/world.cpp
index cc81dbef8..6a8322bb5 100644
--- a/components/terrain/world.cpp
+++ b/components/terrain/world.cpp
@@ -47,7 +47,7 @@ World::World(osg::Group* parent, osg::Group* compileRoot, Resource::ResourceSyst
 
     mTextureManager.reset(new TextureManager(mResourceSystem->getSceneManager()));
     mChunkManager.reset(new ChunkManager(mStorage, mResourceSystem->getSceneManager(), mTextureManager.get(), mCompositeMapRenderer));
-    mCellBorder.reset(new MWRender::CellBorder(this,mTerrainRoot.get(),borderMask));
+    mCellBorder.reset(new CellBorder(this,mTerrainRoot.get(),borderMask));
 
     mResourceSystem->addResourceManager(mChunkManager.get());
     mResourceSystem->addResourceManager(mTextureManager.get());
diff --git a/components/terrain/world.hpp b/components/terrain/world.hpp
index da1004783..4fb724ebb 100644
--- a/components/terrain/world.hpp
+++ b/components/terrain/world.hpp
@@ -116,7 +116,7 @@ namespace Terrain
         std::unique_ptr<TextureManager> mTextureManager;
         std::unique_ptr<ChunkManager> mChunkManager;
 
-        std::unique_ptr<MWRender::CellBorder> mCellBorder;
+        std::unique_ptr<CellBorder> mCellBorder;
 
         bool mBorderVisible;