I dont know if this is already documented but on E1M7 Computer Station you enter a large chamber with a tall column in the middle of it as you approach the column an invisible trigger should set the column to lower and there is a few enemies to kill on top of it.
Using the latest Doomsday engine 1.9.0-beta6.9 the invisible trigger is activated and you hear the column lowering but it does not move!
using the same WAD and the PrBoom engine the column acts as it is suppose to.
I tried using doomsday again with all addons disabled with no affect
This is the only major bug i found in the entire first episode however it stops you from reaching 2 secret areas that you would get to by leaping into the acid off the column as it raises.