Ah that is a very good question.
Ok Using their own words:
"Hit play starts says running then stops. ? Tried changing compat. settings no change. Using Win 10 AMD R9 380 4g card."
"I get the loading circle at my mouse for about 5 seconds and nothing happens. I see the .exe running in task manager at processes but not at applications. Longer periods of waiting doesn't change anything.
" it just loads for about 3-4sec and nothing after.
Clicking .exe does exactly the same thing as when using steam to start.
Eternalstep.exe is a 7.7k big process in my taskmanager after starting."