Some cleanup and a fresh layer of double-sided tape gives the cursor milling fixture plenty of adhesion:
It’s not a Purple Crayon, but it suffices for my simple needs.
Scribbling a (soft!) lacquer crayon over transparent plastic still scuffs the pristine surface around the engraved line, so I tried scribbling the six-pass cursor before peeling the film, as shown above. Unfortunately, the film shreds left around the line either prevent a clean fill or pull the paint out of the ditch as the film peels back:
Peeling the film and scribbling ever-so-gently left a more complete line, but, if you look very closely (perhaps opening the image in a new tab for more dots), you can see the scuffs left by the scribbles on either side of the line:
When seen from the other side against laminated decks, though, the scuffs pretty much vanish:
The red hairline isn’t historically accurate, but I like the way it looks.
Give me some (heavyweight matte) paper and a (lacquer) crayon, put me in a basement (shop), and I’ll be happy for days …