By enabling "Freelook in 3D window" in the preferences screen you can use a noclip style of movement in the camera window. Rightclick in your camera window (or shift+rightclick if you are in 2 mouse button mode) to start freelook mode. The mouse can be used to look around, up arrow is forward, down arrow is backwards, left and right are strafing. You can control the sensitivity of the camera controls in the preferences screen, directional velocity is for movement (forward/back/strafe) and angular velocity is mouse sensitivity. Also you can enable inversed mouse mode here.
Another way of moving backward and forward in the camera window is by using your mousewheel, scroll up is forward, scroll down is backwards. This works in all camera modes, classic as well as freelook.
1.1-TA was the first version to add builting support for mod directories, bringing easy editing capabilities for Quake III: Team Arena. This has been extended to support any mod developement. Simply open the project settings dialog to set the mod directory (among several builtins, Quake III Arena, Quake III: Team Arena and custom mods).
The mousewheel has gotten another new option for the 2D windows. Scroll up is zoom in, scroll down is zoom out.
It is possible to texture faces simply by selecting a texture in the texturewindow and dragging it into the 3D (Cam) window onto the face you want to texture with it.
More GtkRadiant tips and tricks have been gathered on the qeradiant.com FAQ.
Current known issues for GtkRadiant releases are listed in the qeradiant.com FAQ.