Yeah, they're nice xandaxs - that kind of thing.
There's no official FS support for this idea but here's the deal.
The CMM stamp is something you can apply for when you release a map.
Simply post a request in this forum Map test forum
with a link to your map.
The map will be tested against a checklist on clean installs of urt / urt 4.1.1 and the alpha urt hd.
If your map fails any of the tests you will be able to download a zip file containing screenshots of problems and a document containing comments and possible fixes.
You can then resubmit the map after you've fixed up the problems, you can do this as many times as you need before your map is ready for release.
If your map passes all the tests a we'll append some text (blah blah this map passes the CMM test blah blah) to your readme file and if you request it a discrete stamp will be added to your levelshot (optional). The pk3 will be added to the CMM server and you'll be able to download the certified pk3 from the CMM download, you'll also be able to use this link when you release the map.
I've had a couple of offers from people wishing to help test the maps, if anyone else wishes to help out, let me know.
It might help filter out those simple mistakes we all make when we release a map and save some red faces.