Hi!
I’am testing the navmesh cut out. But i guess the rotation is bugged. Without the “Use Rotation” checked it works fine but when i check it, then the circle/rectangle becomes a 1d surface. Can you confirm this?
Likely your navmesh cut is rotated 90 degrees around one of the axes so that the 2D surface is vertical, the surface will be projected down onto the XZ plane, but if it is vertical, it will just be projected onto a 1D line.