With alignment being what it is for people, I’m curious how close you are placing your work to the boundary? The common issue most of us have is that the further from the center you are, the further the alignment is to being true. So if you’re too close to the edge of the printable area, then it stands to reason that you’re actually placing your work in the out of bounds area, but the camera is not relaying that to you within the UI.
For me, when placing artwork to the left of center, I’m gauranteed to engrave further to the left of where I “placed” my work. This goes vice versa for the right side, of course. The further from center I go, the more I notice the variance, so slightly left gives me a slightly off center print, and if I’m close to the edge, I can be as far as 1/4" which is crazy, but I anticipate this.
If you could screenshot the after image of a failed print with your artwork overlaying the engrave, that would be helpful as well. You definitely aren’t the only person this has happened to, and both support and the forum members may have suggestions on what you can try to remedy your particular problem.