Revising a previous sugestion I made here
, I took my time and made a patch:
I added a new MAPINFO property: ForceWiperEffect
Setting this property for a map, forces the Wiper at exit even if the level belongs to a hub. The Wiper shown depends on the user settings (Melt by default for Doom and so on). I know this could be more polished, but it's a start. I used r3757 as a base, so it's possible that the patch could be outdated. Be advised that this is the first patch I've ever made, so if it does not work, please tell me and I will upload the modified source files instead (along with a text file pointing out the lines I added).