Quite a unique map. Admittedly I did use godmode for a decent portion of it. The atmosphere is executed very nicely, complimented well by the music. I first tried it with chocolate doom and I had the same issue of clipping through the first door as well, so I switched to gzdoom. Overall quite nerve-wracking and creative.
Doom #20hours20monsters Speedmapping Challenge » Entries » 20 Hours 20 Monsters - Doomguy's Nightmare