Problem
When launching Apotheon the game doesn't start or crashes.

Solution
The game requires Microsoft XNA Framework which didn't install with the GOG offline installer.
Once you install the XNA framework the game should start.

Tested with GOG offline installer file version 1.3_(22138) with Microsoft XNA Framework 4.0 on Windows 7 SP1 x64.


Microsoft XNA Framework
https://www.microsoft.com/en-us/download/details.aspx?id=20914