Issues with 3D bridges

[Herculine]

I discovered an issue today while playing the Final Portal map by Michael Reid (http://www.doomworld.com/idgames/index.php?id=10130) with build r1346. When I came to the first 3D bridge in the level I was unable to cross it as if an invisible barrier was in the way; I was unable to continue until I used the NOCLIP console command. I later loaded the map with ZDoom and was able to cross the bridge as the author intended. Looking at the map in DoomBuilder I see he used a bit of trickery that might normally be considered map errors to achieve the bridge effect; are such things not compatible with GZDoom or the current SVN build? This isn't a complaint; just thought you guys would want to know.

EDIT: I also checked with r1388 and experienced the same issue.

[Graf Zahl]

I don't get blocked but the bridge certainly has some glitches. Which is not surpising. Its design is fatally flawed. I see no point investigating this problem any further. It's just not fixable