I've found a new possible route on Cellar Zombie by using the ragdoll respawn glitch. With good timing you end up under the yellow ramp at the start of the level, then if you ragdoll on the left wall, there's a slight (1 time in 3 hours) chance that you get teleported near the spot where you clip your head to the checkpoint. For now it's definitely not viable but I think that with practice it could make sub 15 possible on the level. I'll make video about it later today.

The Unused Version of BOX15_435_0X00005, "Level_BoxUniverse" is now playable. The set up is actually the exact same as "Level_Falling". This level, on the other hand is technically beatable as the end goal functions normally. Though, the start of the level is extremely hard so I had to cheat on the first part.

Since I'm not that good at Ben and Ed, I believe people will eventually beat it. My gameplay is on the video below. This was the last unplayable level of the game. Every unused level is playable now.

The Unused Version of the Fall "level_Falling" is now playable. It's a little hard to set up though. My gameplay of it and how to set it up is in the video below