Just finished this game. Excellent work! Most of the time I couldn't even tell that it was a DOOM mod. Lots of little tricks that kept the world seamless.
Every bullet being a projectile instead of hitscan so that Dooms weird aiming system doesn't interfere, the entire world being contained in one map so that end level screens don't interfere, etc.
I am genuinely impressed by the ingenuity of this mod, and I also really loved the lore of the game.