I used the terrorstrike map and changed some things.
FPM attached.
I dont know if the parameters i use come along with a fpm file.. if not, change the waterscript to 158 (yes, somehow these variables are different for my game, but the problem is the same)
Notice there is a hole in the basement floor.. water is below the floor (with 158). Yet.. try and jump in and get out.. sure, normally it doesnt work, so no other outcome this time.. but after a few times trying to do get out (shift-w-space or w-space) i get stuck and cant move anymore.
second thing i notice is my health gets a hit when i get below in the basement, just when you're down the stairs. Same thing happens in my game after i plunged myself 2 stories down in a pool and get out. The moment you leave the water (still standing in 8 (200 +8 in my game) water i get a hit on my health. But that issue was around in 1.19 already. So its older than 1.20
For my 'bug' you get yourself a waterlevel/height of 178, and see what happens.. you cant get out (all the time), and when your trying to get out from where there is no wall to push off of (or something
) you get yourself stuck underneath/besides the floorboard.
Fiddle around with places to get out and the waterlevel between 158 and 198
The behaviour is somewhat different (waterlevels and getting out yes or no) from my game and i didnt notice the heavy shaking i had in my own level (need to check for ledged) when trying to get out via a wall adjacent floor.
Hope i made myself clear, otherwise let me know.
Grts
Anubis