Oh, sorry, my guess is Apple decided to implement some new permissions/security stuff that wasn't there before. Or, perhaps it is trying to start the 32-bit version of Freerider (Freerider still includes both 32- and 64-bit executables for Mac). I tried searching for answer but I didn't find anything definitive, seems like a pretty common problems that some apps doesn't start after updating to Catalina though...
(Still, if the demo doesn't run the full version most likely won't either).