Drape is inverted

I don’t know if this is something that can be answered here, but I am having problems with drape.
Specifically, I am using Gemvision Matrix, a program to make rhino more friendly to jewelers, but for some reason its drape command creates inverted and foreshortened results. If I take the same model to rhino i get the results I expect. I am wondering if anyone knows of accessible parameters that mimic this error so I can try to isolate the problem in Matrix.

In an ideal world I would try the Matrix tech support, but they stopped supporting my version, and the forum doesn’t look active (though I will still try there).

From the Help file for Drape:
The Drape command creates a surface through points defined at the intersection of objects and points projected toward the construction plane in the current viewport.

Any chance your object is on the other side of your CPlane?