How to Install New Version of GTKRadiant
First install a clean copy of Quake 3 Arena or other games which maps could be made with GtkRadiant.
Then install GTK Radiant 1.6.3 on to the folder Quake III Arena\.I mean just extract the folder
I found Gtkbuild but when i search it again cant find its location .its a bug for google .
When you search for
"GTKBuild_v20_full.Exe"
it appears at first result.But if you dont know name of it and search as "Gtk build ,gtkradiant build ,quake 3 build its not able to find it.
Then install this too regular folder.Run GTKBuild and goto options on menu bar
At Program settings Change Location/ name of q3map.exe instead to Q3map2.exe on GTKRadiant folder
Set bspc.exe location as same before.
Set Quake III Arena Folder .
You did it.Congrulations.
Links: GTkRadiant 
İcculus
Good Source with detailed Instructions
3d gtk radiant level designe notes
All the map styles will be availeble now for all of you
And unzip pak0.pk3 into the same folder it exists ( Program Files/Quake 3 Arena/baseq3/).
Then make sure the project settings directory is same directory(.From File Project Settings menu.)
How to import sketchup models maps that resides in Google Earth maps into games that uses GTKRadiant 1.6.3 for making maps (not maps of cartography) of game,and models.
First look at GtkRadiant menu File to import this models with extension of .Skp .3ds collada .
Skp
