This disables the boss's death in L4 ending the game and just advances to the next level.
This seems to be the intent with this mod as the second episode starting at L5 is not defined and the first episode's subtitle advertises the full game.
This is clearly a mapping error - these sectors aren't even supposed to have a sky - No idea why this did not glitch out in the other renderers
Trying to fix this in the renderer is tricky because it involves some unknown render quirk.
This is a lot easier to manage than having them in the code.
For now it piggybacks on the map hack feature, later this should use the same scripted approach as GZDoom.
