Originally posted by ZeqMacaw:

Decompiling of animations and their QC commands are unfinished features because no one knows how to decompile all of them correctly.

For L4D2 weapons, there should be known workarounds, which might include using files from the L4D2 Starter Kits.

Sadly, the starter kits feature no reference file and this way it seems to be impossible to make a mod on custom animations.

So, as of a while ago I started experiencing "bugs" with the decompiler. So far the bug seems to exist for specific weapons after decompiling them (L4D2 default weapons).

After decompiling the sniper rifles (hunting and military rifles), their reference mesh in 3DS Max seems to be a bit screwed up. I imported the idle animation and swapped the default model with another one and exported as a reference mesh. After compiling, there were some weird camera rotations and hands were all over my screen (couldn't even see the weapon normally, much less the map I was playing).

Image of the reference mesh: http://i.imgur.com/AWVaB5I.jpg

The reason I believe this is because of the decompiler is that I tried decompiling the hunting rifle and then compiling it again (with the files I got from the decompile) without modifying anything, I got the same problem.