there is or was a discord server linked on the website, but its gone now. Your best option right now is the ultrakill speedrunning channel in the newblood discord server

edit: its now back

Im not a moderator but you can't modify the game files in any way, even changing sounds

i think it means that every time you get an improved time you have to make a new submission, and if you have already submitted a run and you got a better time while waiting you have to make a new submission instead of editing the old one. Not different for individual level runs

correct me if im wrong btw but thats how i understand it

Im not a moderator but no mods are allowed, the game must be fully ummodded

Thats in the rules btw (i think game rules i forgot)