Some creatures CTD

I have a problem with some creatures because I get a Crash to Desktop as soon as they are spawned.

the creatures are: DEMOCLER.CRE, GORGUA03.CRE, TOBPAR05.CRE and YARMY02.CRE 

Can anyone help me to understand why I get the crash and possibly to fix the problem please???

After check using near infinity I got the following results:

• File: DEMOCLER.CRE  Offset: 5f2h  Error message: 24 unused bytes between Unknown(5f2h) and Item(60ch);
• File: GORGUA03.CRE  Offset: 652h  Error message: 24 unused bytes between Unknown(652h) and Signature(66ch);
• File: TOBPAR05.CRE  Offset: 5f2h  Error message: 12 unused bytes between Unknown(5f2h) and Item(600h);
• File: YARMY02.CRE  Offset: 406h  Error message: 12 unused bytes between Unknown(406h) and Item(414h)

and here is the file TobEx error:

•  

  • ASSERTION FAILED! Return Address: 0x8BB49B File: ObjCreature.cpp Line: 12381 Expression: creatureSize == 0 Message: (null);
  • ASSERTION FAILED! Return Address: 0x8BB49B File: ObjCreature.cpp Line: 12381 Expression: creatureSize == 0 Message: (null)
  • ASSERTION FAILED! Return Address: 0x8BB49B File: ObjCreature.cpp Line: 12381 Expression: creatureSize == 0 Message: (null);
  • ASSERTION FAILED! Return Address: 0x8BB49B File: ObjCreature.cpp Line: 12381 Expression: creatureSize == 0 Message: (null);