I think I fixed the Steam achievements DLL problem. I just changed the source code to unlock the achievement 10 times in a loop, because the third party Steam plugin seemed kinda random. Also a couple of fixes to the BATTLES DLC.
Link: https://steamcommunity.com/games/652410/announcements/detail/3362526602426926379
Complete list of fixes:
SOURCE CODE:
-Fixed Steam achievements problem (I think).
SCRIPTS:
-(BATTLES) Fixed bug where Cooper would not disappear after initial dialogue on plantation.
-(BATTLES) Players starts with machete instead of axe in Loma Larga battle.
STORY FILES: (requires starting a new game)
-(BATTLES) Added a couple medkits in a crate at the start of Loma Larga battle.