+Download the desired game packs:
+ cd ./GtkRadiant/install/installs
+ svn checkout https://zerowing.idsoftware.com/svn/radiant.gamepacks/Q3Pack/trunk/ ./Q3Pack
+ svn checkout https://zerowing.idsoftware.com/svn/radiant.gamepacks/UFOAIPack/trunk/ ./UFOAIPack
+ svn checkout https://zerowing.idsoftware.com/svn/radiant.gamepacks/TremulousPack/trunk/ ./TremulousPack