Why is this relevant? Well, at something of an unexpected loose end, I decided to quickly throw a map together to give myself a chance to play around with UDB a bit more thoroughly and with a bit more purpose than just testing it. UDB performed brilliantly. There were no issues whatsoever that I am aware of.
The map is nothing special; just a couple of rooms really; if that. I think the editing time was somewhere between 3 and 4 hours (it probably shouldn't even have taken that long to be fair, it's not big). It shouldn't take much longer than 5 minutes to complete it with 100 kills, 100 Items, 100 Secrets.
Worth releasing? Meh... maybe? Maybe not.
Why Zygomatic? Honestly, I couldn't think of a name and the map has a lot of MARBLE3 on the walls. MARBLE3 features skulls, the zygomatic process is a bone of the skull with a cool name...
Screenshot:

Download
http://aspectsweb.co.uk/enjay/doom/njzygo.pk3 (a massive 100 KB)
Details
Description: Just a very small map. Not much more than a room really. Marble, metal and rock theme.
New levels: 1 (MAP01)
Sounds: No
Music: No (but changed using MAPINFO)
Graphics: No
Dehacked/BEX Patch: No
Demos: No
Other: MAPINFO
Other files required: None
Game: Doom 2
Single Player: Designed for
Cooperative 2-4 Player: Start spots added but not balanced
Deathmatch 2-4 Player: No
Difficulty Settings: Yes, implemented
Base: New from scratch
Build Time: ~3.5 hoours
Editor(s) used: Ultimate Doom Builder (plus Textpad for the MAPINFO)
May Not Run With: Anything other than GZDoom
Tested With: GZDoom 4.2.4 official and g4.3pre-546-g738b9ceb0
Bugs: None known about - doesn't mean they don't exist though.