GtkRadiant/Getting around in GtkRadiant
Now that you have downloaded, installed and started GtkRadiant, you will probably start to draw around a bit with your mouse, and you will see that where ever you draw on the grid, a red square will appear, now you may think, is this really the program all others made those awesome maps in, the answer is probably yes, so, how is this done, first of all, you have to learn the interface.
This is the 2D Viewport, in here you can either see your map from above, from the front, or from the right. To change the view, press CTRL+TAB or click the button in the toolbar. This is also where you create brushes, to create a brush, just drag with your mouse.
This is the Console where GtkRadiant prints down every major (or minor) thing it's doing. This is very useful if you get error messages or if something else doesn't work like it should. Note that all critical stuff is displayed in red color.