I would like to make a suggestion that the following machines in dragon lairs should be usable by both dragons and bipeds:
essence channeller,
scholar's desk,
gem cutting bench,
smelter, and
stonecutting bench.
Absolutely the crystal shaper and scaleforge should not be usable by bipeds, just as dragons can't use tanning racks, looms, or any other organic resource processing machines.
These machines in biped form are already usable by dragon crafters and dragon lairshapers. Dragon crafters even get bonuses from the beginner, journeyman, and expert versions of these machines, though I've heard that some of these machines are not offering bonuses to dragon lairshapers (I think that was a bug that's fixed on blight).
It should be noted that dragon lairs and biped plots are frequently found near each other, but sometimes plots are closer to resources than lairs, and sometimes lairs are closer to resources than the plots are. This would create a sense of equity between the races.