it's possible to put cegui in darkplaces / nexuiz ?
http://www.cegui.org.uk/

Crazy Eddie's GUI System is a free library providing windowing and widgets for graphics APIs / engines where such functionality is not natively available, or severely lacking. The library is object orientated, written in C++, and targeted at games developers who should be spending their time creating great games, not building GUI sub-systems!

Looks pretty cool, certainly more flexible than the engine's current abilities. I can't comment on what it would take to integrate into Nexuiz but I can tell you that Nexuiz is coded in C and this is C++ so it's not just a quick drop in solution unless I'm mistaken.

Well, Nexuiz's current menu system does have similar abilities, as you see since Nexuiz 2.4; however, it doesn't even have to be written in C, but in QuakeC (otherwise Nexuiz, the game, can't customize it, as DP has to use the menu for Quake too).

In any case, it will probably be impossible to add this to DP. Such libraries are good for making new games using a GUI - but changing an existing game to use such a GUI is usually very complicated to do, if possible at all.