Honestly I think it would be much better to start off fresh and not port any code if we where ever to switch engine, porting code over may sound as an "easier" way to do it, but the things done in this version of torque could be done way more optimized on another engine.
The only problem to that is it would take too long to do so and Blockland was made by like 3 people, that being Baqdspot, Rotondo, and Kompressor.
Its a 3 man group, so if this where to ever even happen, expect it to take a very long time before you even get a "Blockland 2.0"