I just got it too with r555. Screen wipe style was Burn. Can't think of anything else relevant.
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Just tried. I can get the effect with Burn, Crossfade and Melt. Here's a screenshot of how it appears for me. I noticed a zombieman showing through the wall too:
Interestingly, I got that screenshot by stabbing at the printscreen key a as the game started. I say interestingly because I got two screenshots and the first one (Screenshot_Doom_20091017_230300.png) looked normal - ie the effect was not visible - and the next one (Screenshot_Doom_20091017_230317.png) is the one above. I can't say that I noticed the screen appearing normal before the effect but I guess that it must have done.
Most of the time I do not get the effect but when I have a certain file loaded, it seems to significantly increase the chances of the effect happening. The file isn't mine, it was one that I was sent to check something in so I'll send it by PM.
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