Hakureix3

I want to make a rather complicated shaped spaceship, I have tried making a custom shape dae file but it's just wayyyyyy too expensive because of small triangles and even when I make big simple boxes the shape s misaligned with the mesh, even when I export with name orders. So I figured it would save me alot of trouble if I was to make a wall with "prism" shape already in it, which I did and works liek wonders! And then link them to the ship, WHICH I also did and yay, the ship is only 4 prisms! BUT! The ship refuses to stay in "None" physical shape and changes to convex, so I tried getting around it by making a cube, a tiny cube, and make that the physics mesh to see if I could align it somehwere else, and the cube enveloped teh whole ship to my amusement. Basically I want the ship to be phantom-like, as I cannot link phantom objects with non-phantom objects to my understanding as it goes back to being non-phantom and convex.

I built a spaceship and it has a separate interior to the exterior so that I may add textures separately. Although I take them both out of my inventory, it seems difficult to align them the same way they were in Blender where I made them. Is there any way to set them to the same exact position without dragging it to try and align it?