Torque Game Engine 1.5.2 runs well enough on Linux (the Penny Arcade game is using TGE). Torque Game Builder is a different beast... better off to forget that exists. Only one game that I know of has been put out with TGB for Linux & that isn't using the latest version of TGB (I can't get any of the newer TGB builds to compile anymore). As for Torque Game Engine Advanced... that never did run in Linux, probably never will since it doesn't have OpenGL in it.
Right now, Linux support is "community driven" in TGE. It's been that way for a long time now. While that sounds nice, in reality, GG has been very slow in getting patches put back into the engine. Many of the people who have helped out in the past got tired of dealing with the delays.
Back on topic of the game itself above... if TGE was used, it won't be too hard to get a Linux version out.
