When a part of your design is out of the laser area, the Glowforge UI grays it out to show it won’t be cut or etched. This is the exact opposite of what it should do. Look at this snapshot. The objects that won’t be cut are almost invisible (not that the rest is so visible either).
The part that won’t get lasered should be highlighted “Hey, I’m not going to get cut!” rather than made more subtle so you miss it. It should be bright red and blinking. OK, maybe not blinking, but it should be more obvious, not less obvious.
One of my fundamental rules of UX is Don’t Be Subtle. More completely, “Don’t be subtle unless there is a compelling advantage to it.” Here, there is a compelling disadvantage, wasted material when you don’t realize what you’ve done until after you start the job and now it’s too late. Fortunately for me, every time I’ve done this I haven’t wasted an entire sheet.
A related but separate issue is whether there should be an option to cut/etch/engrave part of an object that is part in and part out of the laserable area. I think the former is a bug; this is more of a feature request.