Thanks for the link Cobo, that was very interesting. I noticed Jitspoe even posted there, maybe he can fill me in on some more info about the XReaL engine
edit: I got the maps to compile by downloading a few opensource libraries, compiling xmap.exe, then running xmap -map2bsp <map name>.
Although, I had to use the visor model from my Q3 installation,
Anyway, it looks fantastic, despite not having any textures yet..
Edit again: after asking in IRC for the textures, they gave me the directory for maps and textures.. and everything else you need to get up and running, so Cobo, knock yourself out
http://xreal.varcache.org/base/