First, let us consider the fact that for the first time ever, as a species, an entirely playable and full version of the Half-Life 2 Beta campaign is in our reach. Half-Life 2 Beta Minimalist mod is a COMPLETE RECREATION of Half-Life 2's original storyline, that follows HL2 Early Geography and 1999-2001 storyline for an accurate and fulfilling experience, while retaining a modest and minimalist design.
go to xen please
So the original concept art of a teleporter features a "door opening to light", and you got the idea right. But doesn't it look like a Gman's "door to heaven" which he uses all the time? Could he use some kind of a teleporter device, similar to Kleiner's one, with the very same lighting effect?