[Jester]

I agree, it does have limitations. Mikey's mech might just be an example. it made it from his imaginings, but soon malfunctioned because the physics just weren't there. If they had made a time travel devise with the Transcendental Lathe, there's no guarantee it wouldn't have malfunctioned and sent them all back to the stone age.

EDIT:
Question: did they use the TL to create anything with moving parts? The weapons are pretty basic, any major device could be too complicated for the poor lathe.