to test a map without spending like an hour compiling, go to export by clicking qbsp-nofill in the export menu
then, c:bsp/quake2/mapfiles and there will be a file in there called yourmapname.bsp (whatever you named your map) then, paste this file into the c:/games/paintball2/pball/maps or wherever you have paintball installed. then, your map should be in the maplist. (pasting the .map file in the folder will do nothing, you have to use the .bsp file)
as for the directories, make sure the .map file you are loading to bsp is saved in the "mapfiles" folder i mentioned earlier. otherwise, bsp will refuse to export it