When I try to 'Cut/Pocket using Closed Contour' the geometry applied to the attached cabinet, I get the error shown in the screenshot. Not sure how to post the DXF that I'm using.
The filleted corners have two layers which is causing the problem. Go to contour, zoom way in on one of the corners and choose erase single and mouse over one of the segments (the fillet in the corners is very many tiny segments) and erase the segment and you will see there is another below it.
I would create this geometry in eCabinet to cure this problem. You will have to do it in contour though as the geometry cut is still broken in eCabinets. (you can't fillet the inside corners.