I don't know how best to point this out, but I'll do my best.
The Yor medium hulls have a few glitches. The first one (three prongs in the front) is fine, but the second and third have some odd hardpoint problems. One of them - the third, I think - has one of its hardpoints reversed (thus requiring a flip, a 90-turn, another flip, and another 90-turn ... not really a big deal) and the other (looks like a sled and is characterized by two downward fins/spoilers in the front as part of a larger piece) has some serious hardpoint problems. On the lower spoilers, for example, placing something there will actually place the object on one of the upper hardpoints. Trying again will glitch the design and prevent removal of those components. Other hardpoints on the hull will produce similar results - basically, the object goes where you don't want it to go and it's impossible to place it correctly, even if the mouse-over preview works fine.
I'm not sure if any other race hulls have this problem as I haven't played as any other race yet. Just a heads-up.