Note: a word is considered to be 32 bit long.

Header (4 words):
word: number of words in code block
word: number of words in integer literal block
word: number of words in float literal block
word: number of words in string literal block

Body (variable length):
code block
integer literal block (contains a collection of 1 word long integers)
float literal block (contains a collection of 1 word long floating point numbers)
string literal block (contains a collection of strings of variable length, word-padded)

Code bit-patterns:

3322222222221111111111
10987654321098765432109876543210
00ccccccAAAAAAAAAAAAAAAAAAAAAAAA segment 0: 64 opcodes, 1 24-bit argument
01ccccccAAAAAAAAAAAABBBBBBBBBBBB segment 1: 64 opcodes, 2 12-bit arguments
10ccccccccccAAAAAAAAAAAAAAAAAAAA segment 2: 1024 opcodes, 1 20-bit argument
110000ccccccccccccccccccAAAAAAAA segment 3: 262144 opcodes, 1 8-bit argument
110001ccccccccccAAAAAAAABBBBBBBB segment 4: 1024 opcodes, 2 8-bit arguments
110010cccccccccccccccccccccccccc segment 5: 67108864 opcodes, no arguments
other bit-patterns reserved

legent:
c: code
A: argument 0
B: argument 1

Segment 0:
op  0: push arg0
op  1: move pc ahead by arg0
op  2: move pc back by arg0
opcodes 3-31 unused
opcodes 32-63 reserved for extensions

Segment 1:
opcodes 0-31 unused
opcodes 32-63 reserved for extensions

Segment 2:
opcodes 0-511 unused
opcodes 512-1023 reserved for extensions

Segment 3:
op    0: show message box with message string literal index in stack[0];
         buttons (if any) in stack[arg0]..stack[1];
         additional arguments (if any) in stack[arg0+n]..stack[arg0+1];
         n is determined according to the message string
         all arguments are removed from stack
opcodes 1-131071 unused
opcodes 131072-262143 reserved for extensions

Segment 4:
opcodes 0-511 unused
opcodes 512-1023 reserved for extensions

Segment 5:
op   0: store stack[0] in local short stack[1] and pop twice
op   1: store stack[0] in local long stack[1] and pop twice
op   2: store stack[0] in local float stack[1] and pop twice
op   3: convert stack[0] from integer to float
op   4: replace stack[0] with integer literal index stack[0]
op   5: replace stack[0] with float literal index stack[0]
op   6: convert stack[0] from float to integer
op   7: invert sign of int value stack[0]
op   8: invert sign of float value stack[0]
op   9: add (integer) stack[0] to stack[1], pop twice, push result
op  10: add (float) stack[0] to stack[1], pop twice, push result
op  11: sub (integer) stack[1] from stack[0], pop twice, push result
op  12: sub (float) stack[1] from stack[0], pop twice, push result
op  13: mul (integer) stack[0] with stack[1], pop twice, push result
op  14: mul (float) stack[0] with stack[1], pop twice, push result
op  15: div (integer) stack[1] by stack[0], pop twice, push result
op  16: div (float) stack[1] by stack[0], pop twice, push result
op  17: convert stack[1] from integer to float
op  18: convert stack[1] from float to integer
op  19: take square root of stack[0] (float)
op  20: return
op  21: replace stack[0] with local short stack[0]
op  22: replace stack[0] with local long stack[0]
op  23: replace stack[0] with local float stack[0]
op  24: skip next instruction if stack[0]==0; pop
op  25: skip next instruction if stack[0]!=0; pop
op  26: compare (intger) stack[1] with stack[0]; pop twice; push 1 if equal, 0 else
op  27: compare (intger) stack[1] with stack[0]; pop twice; push 1 if no equal, 0 else
op  28: compare (intger) stack[1] with stack[0]; pop twice; push 1 if lesser than, 0 else
op  29: compare (intger) stack[1] with stack[0]; pop twice; push 1 if lesser or equal, 0 else
op  30: compare (intger) stack[1] with stack[0]; pop twice; push 1 if greater than, 0 else
op  31: compare (intger) stack[1] with stack[0]; pop twice; push 1 if greater or equal, 0 else
op  32: compare (float) stack[1] with stack[0]; pop twice; push 1 if equal, 0 else
op  33: compare (float) stack[1] with stack[0]; pop twice; push 1 if no equal, 0 else
op  34: compare (float) stack[1] with stack[0]; pop twice; push 1 if lesser than, 0 else
op  35: compare (float) stack[1] with stack[0]; pop twice; push 1 if lesser or equal, 0 else
op  36: compare (float) stack[1] with stack[0]; pop twice; push 1 if greater than, 0 else
op  37: compare (float) stack[1] with stack[0]; pop twice; push 1 if greater or equal, 0 else
opcode 38 unused
op  39: store stack[0] in global short stack[1] and pop twice
op  40: store stack[0] in global long stack[1] and pop twice
op  41: store stack[0] in global float stack[1] and pop twice
op  42: replace stack[0] with global short stack[0]
op  43: replace stack[0] with global long stack[0]
op  44: replace stack[0] with global float stack[0]
opcodes 45-57 unused
op  58: report string literal index in stack[0];
         additional arguments (if any) in stack[n]..stack[1];
         n is determined according to the message string
         all arguments are removed from stack
op 59: store stack[0] in member short stack[2] of object with ID stack[1]
op 60: store stack[0] in member long stack[2] of object with ID stack[1]
op 61: store stack[0] in member float stack[2] of object with ID stack[1]
op 62: replace stack[0] with member short stack[1] of object with ID stack[0]
op 63: replace stack[0] with member short stack[1] of object with ID stack[0]
op 64: replace stack[0] with member short stack[1] of object with ID stack[0]
op 65: store stack[0] in member short stack[2] of global script with ID stack[1]
op 66: store stack[0] in member long stack[2] of global script with ID stack[1]
op 67: store stack[0] in member float stack[2] of global script with ID stack[1]
op 68: replace stack[0] with member short stack[1] of global script with ID stack[0]
op 69: replace stack[0] with member short stack[1] of global script with ID stack[0]
op 70: replace stack[0] with member short stack[1] of global script with ID stack[0]
opcodes 71-33554431 unused
opcodes 33554432-67108863 reserved for extensions