According to https://support.snapmaker.com/hc/en-us/articles/360041252474-CNC-Carving The CNC outline option should look something like:
but when I try the same file with the outline option it appears to outline each individual line segment.
Looks like it needs to be a closed path for outline to work properly
It would be nice to get some detection for 2 points in the same location, but I can just edit all my files to make sure they are all closed polygons in the mean time.