UE1 - UT Mover occasionally does not move

There is a problem with the lifts I made in my map, 9 out of 10 times when you step on them, they move up without a problem, but occasionally they will just stay down. The moversounds play, although it never seems to end looping and despite stepping on and off them a few times it does not take you up. Then 3-4-5 seconds later, the lift does go up regardless of the player being on it or off it. To maybe eliminate some confusion, this is not like the bug on DM-Curse][ where the 'big lift' sometimes looks like it is down, but has in fact moved up.

I have this problem with both elevators in my map, leading me to believe I must be doing it wrong I'm sorry if my explanation of the problem is a bit vague, but the problem is a bit vague ^^ I have changed very few properties of the movers, tried placing the brushes as "mover" and "elevatormover" changed them from bumpopentimed to standopentimed, but all to no avail!

Has anyone experienced a similar problem before or know how to fix it? Any help would be greatly appreciated! Thank you

The map contains three movers, of which two are elevators. Neither of these is overly complex I would say, one is built out of 3 additive cube brushes, the other out of 4 cubes and a slightly rounded shape, as it had to fit into a cylinder.
I've not had the flickering or invisibility problems with my movers, they are always there and visible (the bases aren't properly lit, but that's the way unrealed always seems to work).

That said, I've re-made the area around one of the movers, and I've not had this problem happening since (but I cannot be certain it is fixed because in 20 minutes of testing I got lucky ^^). If the remake is somehow responsible, the main changes were that I made one subtractive brush for the mover to go through, where there were two. And also I changed some semisolid pillar brushes around that were flush against the top of the mover, if it was in key 1.

If this didn't fix things, there is one part of my level/mover design that makes me think it might cause problems: one of the movers moves through a zone portal. Could that cause problems?

Thanks for your assistance, and I hope to report back soon with a conclusion on my current attempt to fix it.

I have about an hour of gameplay done extra now and the problem has not recurred (where it would show itself once per 3~4 minutes before), so it seems that simplifying the geometry around the elevator has removed the issue. The movers themselves were never changed, which means the lift being somehow 'stuck' down was a BSP error of sorts from the surrounding area. The other option would be the semisolid pillar it touched at the top was to blame. Either option seems quite unlikely, but editing them removed the problem.

But the problem was just very weird to begin with. The player wouldn't fall through the elevator, nor would it disappear, it would just wait at key 0 (base) for a few seconds after being triggered (by a trigger, or by bumpopentimed or by standopentimed) before realising it was supposed to go up as well as play the moversounds. Whereas in most occasions, it would send the player up without problems.

Ohwell, case closed it seems. Thanks for the assistance!