make sure you have set up your path to the game correctly under “file/project settings” and you have
selected ET as the game to map for in “edit/preferences/globals/game settings”. in “edit/preferences/
other/bsp monitoring” check “run engine after compile”. this will fire up the game and load the map
you have compiled. to easen things a little you might want to put an autoexec.cfg file into the /main
directory of your mapping et installation with the following in it:
set developer 1
set sv_pure 0
set g_gametype 2
this will save you from entering those values every time in the console and basically enables you to
load maps that are still in developement (hence plain .bsp files instead of packed .pk3)…
now with all that set up, load your map into radiant and hit “Q3Map2: (single) BSP -meta”. this should
pop up some little black windows showing geek stuff scrolling through and finally, when done, load
up the game with your map. if the map doesn’t load, you get some error messages or the game freezes
when you try to enter the limbo menu… don’t hesitate to use the search or even google… those
questions have been answered maaaany times, i’m sure you won’t be the first one who runs into those 
gl