I banned this user. I didn't spend a full year on the game (not including the time I photographed for it) to put up with this kind of crap. I added customizable actions keys to PREVENT key jamming, if somebody have a keyboard that can not handle up+left+s, it's very likely that it can e.g. handle up+left+shift. This is unrelated to the ban though, I added that for the arrogant comment about the "worst controls in the history of all platformers", as if he have played every single one of them, and knows mine is the worst.
I do encourage people to tell me about potential problems about my games, but not by using superlatives about how horrible it is compared to everything else on the planet. For that I'll just ban without warning.