And after coming back for "one last run" before heading to bed...
Apparently Greg only breaks the framerate on the "you died" screen if you die at the start of the fight. If you get far enough before dying, he doesn't break it.
Hey thanks for playing! Yea remapping keybinds is definitely a priority, especially for keyboard and mouse. Also Ill definitely look into stopping the Greg fight from breaking the game!
I fought Greg 5 times last night, only had the game-breaking bit once (the framerate issue happened on the "you died" screen so I don't count that). Not entirely sure of reproduction steps, but hope my info helps?