Mod troubles

[SpartanISW108]

hello all, this is my first post here

I could really do with some help with a mod I'm making, I'm trying to make the Infiltrator from fallout 3 into New Vegas, I have successfully added the normal FO3 AR into the game Iron sights and all.

 

I have edited the model of the Infiltrator (In Blender) to include iron sights off the standard Fallout 3 AR as I want to make the Infiltrator to be make using weapon modifications, I have the model all made and ready,

I put it onto nifskope and it all appears to be fine and well (please note I'm not an expert on NifSkope)

 

However, when I try and add the .nif onto GECK it causes it to insta-crash with no error message other than ".... has stopped working"

 

Can someone please help me with this as I need this to work. Or could someone please do this for me (remove the suppressor and scope off the Infiltrator and add a flash suppressor and iron sights off the default rifle)

 

Thanks in advance.

 

Ilyasw