[DevExpress Support Team: CLONED FROM T850171: Vector skin element borders render badly at high DPI scaling when a non-default palette is set ]
I have attached an image showing the artifacts left over when you mouse over and out of the first item in a gallery. To make this happen you just need to mouse over and out several times, sometimes from different edges, the artifacts left on mouse out out vary, in the screenshot the top portion of the hot highlight is still present.
This is probably a different issue to the original report since i was able to reproduce it just by starting the Outlook Inspired App, no need to change palettes.