Some extra info would be most useful to try diagnose where it may be wrong. For instance: 1- What OS and antivirus are you running? 2- Are there any mods installed? It should work with mods fine, but if some mod is using bad syntax that could possibly trigger errors. Also would suggest try running directly from the install folder (\AMS\SeasonTool), as opposed from the Steam launch option - see if that works any differently.