For anyone trying to run this on windows, and getting the "code execution cannot proceed because libwinpthread-1.dll was not found" error, I was able to get it working by:
- Running the installer ("AfterMath_Win64_1.0.0.exe").
- Downloading the missing dependency "libwinpthread-1.dll" from dll-files.com.
- Unzipping the dll and moving it into the game's install directory ("C:\Program Files (x86)\AfterMath").
- And then running the game.
It seems like the installer doesn't include it for whatever reason. Anyways, I enjoyed it! Hope others can too. Here's my playthrough: