The triggers that spawn the enemies are really thin, so thin that the slight teleport you get when you mount a rocket is enough to put you past the trigger. I dont know the exact lineups for the ones in 7-2, thats something you could ask grim in the ultrakill discord server
record runs are done on the violence release patch (12/20/23)
curved ceilings are thin, so if you have the front of a rocket out of bounds, getting on the back end of it should tp you through the ceiling
in 6-1 you dive towards the arch, place a rocket as you hit the ceiling before it, then walljump or wallbounce off of the arch to send you onto the rocket.
hopefully that should send you out of bounds, but sometimes you get stuck in the ceiling
the red sections on the chest and tail of the him take triple damage
you need to get hit by the first projectiles just before you shoot the overpump so you dont go flying. dont dash because it makes the maurices track you and the projectiles dont get reflected