Experimenting with some of the shapes I have been using as Avatars I deep engraved and pierced one side and flipped it over and engraved the other side. Getting the rotation correct was a big issue and now that we can use both computer and tablet at the same time without crashing made it possible to rotate and see the result without running back and forth between rooms.
Even sloshing around in the kerf made for a challenge. However, It did appear as 2 separate cases rather than 2 views of the same case, good in that the tablet could be zoomed in more, not so much that the tablet was very slow and clumsy and moving the view instead of the positioning was very much a challenge.
One thing that was odd was that of course the front and back were exactly the same engraving, the same speed, the same location, everything. I did the job in three parts, just the engraving,(not knowing if it would take another pass) then just the cutting out, then flipping over and doing that same engrave a second time.
The first time took precisely one hour and the second one hour and 40 min. It was not a concern to freak out over and complain but it was odd.
I thought the alignment thing was solved by simply cutting a limited-symmetry [rectangular, most commonly] outline on the first pass, flipping, then cutting the radially symmetrical circle?
Was there a reason why you couldn’t do that here?
The trouble with radial symmetry is that while in theory there are nine ways it can find symmetry there are 351 ways that are not symmetrical and even a degree off is a problem so it s a lot more.
On top of that the only way to see that it is symmetrical is close up in the GFUI so that was quite an issue as the computer is several rooms down the hall from the Glowforge.
That is why I brought in the tablet but even then it was iffy as I had to bring up the design that was in the computer and refocus and then open the lid rotate it a bit close the lid and refocus again, which in fine detail was still a bit different each time and I used 3 focus cycles each time to get it as accurate as possible.
Perhaps an inverted small triangle on a side to index with. As in cut outline first, flip and burn through the connection point on the second pass. Just a thought…