P3D v4 Airport ground poly...Y and Z axes flipped(?)

So I decided to try my hand at scenery design and put together a rather basic ground poly. It was constructed in 3ds Max oriented with the positive Z-axis up, as all FS models should be (to my knowledge anyway.) After importing it to MCX as an MDL file, it looks just fine. But once I compile it to a BGL with the ground polygon wizard, it shows up orthogonal to the ground in the sim, as if the Y and Z axes somehow got flipped in the process. All of my MCX settings appear to be the same as in several ground poly tutorials that I've seen, although I do get an error message about my polygons not being at ground level...but I don't have the "bring to ground level" option in my GPW dialog. The whole object is verified to be flattened to exactly 0 meters on the Z-axis. Arno, if you happen to come across this, is this a known bug? Or will a scenery developer be able publicly embarrass me by pointing out an obvious solution (besides rotating my model and building on the XZ plane, of course.)

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