Why??

so cant get into game because it cant find steam yet it was installed from steam any tricks to get this working?

I'm having a lot of trouble figuring out a control scheme for rhythm sections that will let me comfortably and intuitively match the patterns. ABXY (Xbox controller) works well enough - except when I need to rapidly hit two at a time in succession. Then it's a matter of my fingers not contorting fast enough to keep up. I'm not a pro rhythm game player by any means - does anyone have any decent suggestions here?...

Game starts off in Borderless Fullscreen but after 2 seconds the screen goes black. If I alt tab in and out then I'll get visuals again for 2 seconds before it repeats. I was able to do this until I reached settings and set myself to fullscreen only and I can now see permanently however doing this breaks alt tabbing and it no longer works....

- I haven't unlocked the Theremin character yet (Meoo?), no idea where to find a power source. - I fed the big star and did all the devil levels, got both tapes and the Traveler. Is that it? In the alt version of the final level, the King got blown away but no credits rolled? Where are the credits? Are there credits? I still have the last five songs locked in the hub too......