I just stumbled across a document called "Notes on Torque Game Engine" that appears to be unofficial documentation.
It's a 71 page word document that appears to contain:
- history of the engine
- details of scripting in Torquescript (including some very handy datablock/object/function references)
- datablocks and the class/type system
- examples! (animation, teleporter, racing, door, weapon, players/bots, damage, rifle scoping, capture the flag, AI system)
- GUI creation
- exporting models so they can be used ingame
Download - It's hosted on a random site I found on Google.
Word 2003 Document (.doc), 1.1 MB