I bought steam copy of Mulaka today, and I instantly regretted, since I could not get pass the title screen. Game didn't respond to my input. I previously had problems with AER -Memories of Old, of similar issues. I got my money back, but that makes me wonder - does low poly graphic - which I think is gorgeous - have issuses with my new comp?

I see on pcgamingwiki that they are both Unity 5 games and Unity engine is kinda crap sometimes (many times :P ). Check other Unity games that you might have and test how they run.

Unlikely. Did you install to a folder outside windows folders, e.g. C:/mygames. Enable directplay. Install the required c++ extensions (32/64 bit ones are different). Install all required components e.g. Physx is one that can sometimes play up. I note this game is recent and supports win10 so you should have little issues. Check the subforum also.
One other thing, check your graphics drivers and make sure your system is sufficient to run the game. Onboard graphics are always a ballache. Me I favour nvidia and not had any issues in years.