Okay, so from what I know the developer decided to change the engine the game is running on. That's why you might think the steam version is missing some things that you can see on some of the screenshots here, but that's just old screenshots before the engine update. I'm sure these things will come back someday, but if you wanna see what they were about you would either need to find some gameplay of it or find and download an old build of the game. I honestly would rather wait and surprise myself rather than do that tho. And ye, I never played before the engine updated so I don't know what the investigate and arcade stuff was all about myself.