Guess the game wasn't successful enough given you already put it in a cheapish bundle less than month after release? That's somewhat unfortunate as it looks interesting, just not what people tend to play nowadays.

Your Game does not start directly from Steam for me, if MSI Afterburner (including RivaTunerStatisticsServer) is active. It does start with active Afterburner from the game folder (but obviously removes the ability to gain achievements). Deactivating Afterburner removes the Issue. Windows 7 x64 MSI Afterburner 4.3.0 RivaTunerStatisticsServer v6.5.0.8709...

In the level with the hellmouth furnaces, dead body piles, etc - the 'crouch' prompt appears where you're supposed to put a rat in a hole with Hero while Horatus stands on the left panel to reveal this hole. This puzzle doesn't work - can't put the rat in the hole, and you get the 'crouch' prompt even when crouching already and using the rat. ...

I would suggest the option to skip cutscenes. Having to watch them in Full every time you restart a level or just replay the game can be annoying.