You must remove speed pull magazines in previous version if you applied any of them to the weapons before updating when the changelog said so. It can cause the game to crash on launch.
Alternately, you can use The Fixes to prevent the crashing from custom attachments.
List of supported weapons:
Spoiler!
Assault Rifles
M308
Commando 553
Eagle Heavy
Clarion
Lion's Roar
Valkyria
Gecko 7.62
KS12 Urban
Little Friend 7.62
Falcon
Gewehr 3
SMGs
Compact-5
CMP
Signature SMG
MP40
Chicago Typewriter
Swedish K
SpecOps
Jacket's Piece
Cobra
Micro Uzi
Jackal
AK Gen 21 Tactical
Blaster 9mm
Kross Vertex
Tatonka
Patchett L2A1
Uzi
Known issues
Due how the file setup, it does not support custom animation.
However, you can replace the files with this mod in order to make this mod compatible with some animations (listed in the link)