I completely understand the dilemma. ha! I’d have to think about this a little more… but if I was in a bind, here’s how I would approach it. I’d place a sacrificial 1/16" piece of clear acrylic on top of your board (with the crumb tray removed). Then, I’d score the outline of the shape onto the acrylic. You’ll see your board under the acrylic. Then, based on where the line ended up, you might need to budget your board slightly and rerun the scoring. It should take about 3-4 attempts to get it right. Once, you’re spot on you can remove the acrylic sheet and do the actual engraving. If I think of a better way, I’ll let you know… I’ve used this technique before when engraving knife handles or weird/not-flat shapes. I started filming a Glowforge course and I’ll be sure to find a better way to do this Also, don’t forget the No Math tool: No-Math Focus Ruler - it makes everything much easier.