I am no Inkscape pro by any means. I import my png files to create an svg file (files usually include both cut and engrave paths). My cut paths always come out with a double line (can only see this once imported to the interface and zooming in to at least 300%), prompting my GF to cut twice. My stroke thickness I intend for my cut line is between 3 and 4 pt, anything thinner than that, Inkcape (for me) does not create a continuous cut path. Please walk me through your process in Inkscape for files including both cut and engrave.
(ps.: I always go to Path-Trace Bitmap-Multiple Scans-Colors, and remove the background).