Question trying to edit .ff files in mw3 with FF viewer and got issues

[WiseOldMan]

(title)
simple post, i am trying to edit .ff files for mw3 with FF viewer and some of them open but have nothing inside them no files etc
some open but got something like this

 

[JayCoder]

it sounds and looks like its not decompiling correctly.... may want to get the source of .ff viewer and rebuild it...

 

[WiseOldMan]

it sounds and looks like its not decompiling correctly.... may want to get the source of .ff viewer and rebuild it...

I just so happen to have the source code, but I am nothing when it comes to coding