Felix Griffin's Editor Mod
I haven't figured anything out. I had another computer FGEmod used to be on and tried copying global_ents from there; it was older than the one on the computer I was trying to make the map on, but apparently not the correct old one because I still got the dotty cubes effect.
If you still have that copy try copying over the big observation room, I think it's called observation_room_sendtor or something like that.
Hey, that worked! 
Awesome!
I copied the vmf and the vmx, I'm not sure if the second one was necessary but the first one's date differed by several months.
EDIT: Something seems to be a bit wonky with the portal detection. I can't quite get a handle on what exactly is wrong, even after making a map to specifically test it in. It seems like a portal placed up against a wall really far away from the sendificator won't work, but if I put a portal on the ceiling or floor adjacent to that wall it works fine. And when there's more than one sendificator in the map, they work fine, but behave that way with respect to the walls far away from the first one placed...I think. I doesn't seem like the length of the laser is an issue, since I could use reflection cubes and go much longer distances than the portals would have gone, and it doesn't seem like distance from the main observation room has anything to do with it, so..yeah. I dunno. Think I can probably work around the issue anyway.
It's not from the first Sendificator, it's from the primary observation room. Since there can only be one of those, I put the portal detector in that instance. I was trying to make it bigger when I seem to have broken it with the blue bubble things.
I think I fixed the problem now, try using the one in the attachment. I think it'll work. It will definitely remove the bubbles.
EDIT: Also, I forgot to mention, but if you have a portal behind the observation room the Sendificator won't detect it. So keep them in front.
Excellent, now it works exactly as I hoped it would. Turns out I did have the observation room in a bad place; now none of the chamber is behind it.
Thank you very much for fixing this.
Hi Felix!
I'll post probably a hilarious question, but I have not found the answer so far to it: how does the portal deflection cube work? when I shoot portals to it NOTHING happens... It must be something I'm doing stupid. Any help, please? 
I think the portal deflection cube prevents portals from being placed under it, although initially I thought it would deflect portals too.
It should, but I made a stupid programming error and left out the global_ents it needs. I'll make sure to send that over to Ben for the next BEE2 release.
Thank Felix 
I am really eager to use that thing in a series of chambers. Already planning them.