As Rich says, Opulent accepts them. You can view them as just a different category of demos.
Personally, I think that if a map that was designed to be played with the original exes, then port features that enable a player to take unintended shortcuts (or, e.g., to avoid taking damage while crossing nukage) should not be used on that map. For instance, Doom2 map07 UV Speed with jumping allowed is a bit silly.
Some of these things are kind of marginal though. Crossing a room jam-packed with monsters by running over their heads is obviously a much bigger deviation from the intended gameplay than happening to move over a single monster. That was something I felt uneasy about when recording on H2H-Xmas map04 in Legacy. At one point you drop down into a passage that is likely to have some sergeants in it. Chances are that you will walk over one of them. However, when I recently recorded on the same map with Doom2.exe compatibility, it didn't make much difference: I happened to "squeeze" past one of the sergeants, and found him unexpectedly behind me in any case.
I dunno; it's a matter of judgement. If you feel you are benefiting unfairly from port features, and that bothers you, then it makes sense to make a change of some sort. If you're happy with the way you're recording and like the results, then continue in the same way. We record demos because we enjoy it, after all. Just be aware that a direct comparison with Doom2.exe demos may not be very valid (my sn26-038 recorded with Legacy is grossly inferior to Vile's sn26-038, for instance, since I was able to run underneath the cacos).
In case you're wondering, it does bother me that one doesn't run at the same speed in prboom as you do in Doom2.exe. It's only a small difference, but it is a difference. Some port features can't be turned off, and then you just need to decide whether overall you are happy staying with that port.
Note that port features can make things more difficult. Try recording a Max using MBF or Prboom with enhanced monster AI, for instance.
You specifically asked about Freelook and look up/down. When I used Legacy (with mlook), I would always avoid shooting switches (and boss brains) from places where the player wasn't meant to be able to shoot them from. I also tried not to use splash damage from mlook-aimed rockets to kill monsters I shouldn't have been able to hit at all (always difficult to be sure though). Likewise with rockets that hit the ground and damaged monsters that way - I didn't do it deliberately, but it inevitably happened sometimes.
Last edited by Grazza on Dec 10 2003 at 23:36