VERY complex room over room ? for ZDOOM

Look at this screenshot:

http://www.cybernetic-chaos.8k.com/images/screen8.jpg

okay... here's what I would "like" to see, although I'm beginning to wonder if it's even possible..

Currently, there is only ONE possible way to get to the upper floor of the balcony, and I've set up a linedef that switches a trigger to "player on the upper floor"/"player on the lower floor" each time the player crosses it, that way the scripts will know where the player is when you try to activate/deactivate the upper or lower switches (each switch is respective to it's side-by-side door)... now, the switches work fine both ways (activation, deactivation) but the real problem is making each forcefield impassible without setting the "impassible" switch on the linedefs, because that way, if the player had deactivated a switch on the lower level he could freely enter and exit the room, and then go to the upper floor and still be blocked by the active forcefield directly above the already opened door (or vice versa).. I think the easiest way to do this would be to create a map spot and each time the switch was "reactivated" the map spot would spawn an invisible bridge thing, to effectively block entrance or exit from respective forcefield... now this brings 2 questions to mind:

1) What is the name of the invisible bridge thing? (so that I can use the SpawnNoFog() script with it)

2) Okay, when the map starts I could easily already have the invisible bridge things blocking the forcefields, and when deactivated use the Thing_Remove() command to take them out.. now the tricky part.. when I spawn another one after the switch has been thrown again, thus RE-activating the forcefield, wouldn't I have to spawn the invisible bridge thing with a tag, so that I could use the thing_remove() commmand next time the forcefield was deactivated?

Well, any suggestions, ideas, or solutions? PLEASE let me know, because this is getting very frusterating and I definately want to make it happen.. I know there's a way! There has to be!!!

Thanks all, and please, tell me what you think!

what the hell is the crap in the pic? it looks like my dog's garage with a bunch of chewbones

What? The pic didn't turn out right?

1) What is the name of the invisible bridge thing? (so that I can use the SpawnNoFog() script with it)

It's called Thing 9990, but I'm not sure it has a thing name. Until recently, it could not be spawned, but there was talk that ZDooM will/does support spawning any thing. Check ZDooM forums.

2) wouldn't I have to spawn the invisible bridge thing with a tag, so that I could use the thing_remove() commmand next time the forcefield was deactivated?

Yes, you'd need to tag your spawnable. Again, until recently you could not tag a spawned item, and I don't believe anything has changed. So I'd say you're out of luck.

Btw, the picture you have is very dark, so it was difficult to see what you were talking about.

Well, I posted on ZDoom forums and Randy replied, telling me that it was "untested" but, it would probably work... hell yes! ZDOOM has infinite power over the Doom world!!! AHHHHHHHHHH!!!