How do I use the nifty-neato built-in map editor that came with Tribes 2?
Simply start a server (preferably a LAN server with a player limit of 1) in the map of your choice and hit Alt+E. A good mapping tutorial can be found here: http://hosted.tribalwar.com/zear/mapeditmain.html. We recommend keeping Tribes 2 in a window and bringing up a browser to http://www.tribes2maps.com/browser/index.html. One note for those who have used the Windows version: to select a SimGroup into which objects should be put, Alt+Click does not work on Linux. Alt+Shift+Click does.