Hi Michael,

This looks like another case where the 3d Mech eng apps that I've used don't really follow that 'Autocad philosophy' (if you can call it that)
for example in NX if I have two modeling sessions open, one is empty and the other has a rectangular planar surface lying on the XY plane, I copy this surface then go to the empty session, rotate the work co-ordinates 90° around X then when I paste the surface it will come in on the current XY plane but in absolute it is actually on the ZX plane.

That's the only way I can explain it, hope it makes sense.
If you need more info I'll have to show you graphically.

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