This is the Windows installer of GtkRadiant 1.5.0 level editor, supporting most of the id Tech engines driven games.
GtkRadiant 1.5 has wrapped up development and version 1.5.0 is the last stable release. GtkRadiant 1.5 installs with a universal installer for all supported games. Separate "gamepacks" must also be installed for the required game SDK files. The SoF2 gamepack is available here: SoF2-Example-Maps-2004-07-18 other Archived Versions here.