Hi. I have been struggling with this problem for a long time. I have certain files that I try to print. I get the “Scanning Materal” box, then “Preparing Design” box, then NOTHING. It just returns back to the main screen. No error. No indication of what I am supposed to do. Here is a video.
I am assuming that it has to do with the file being to complex. I don’t know how this works… because as you can see in the video that the first print had double the number of objects.
I’ve had this happen and fixed two ways. Most often refreshing the browser helps. In another case which doesn’t look like it fits your issue and it took a lot longer to not do anything, I had multiple copies in my svg so that I could cut several at once. Only after I made the svg only one copy, and then copied multiple times in the GFUI, did it proceed.