Well that’s a problem if you have lots of artwork you want to show. The slide shows get very large and so you have a few shows, and then you want to loop them all, right? Impress does not support that. So I wrote a program to help.
QtShowRunner runs a sequence of LibreOffice Impress slide shows one after the other in a loop. Currently it runs on Windows but soon the plan is to move it to Linux Mint.
See my original question about this problem here:
After no solution appeared, I wrote a program to do it.
Here is a shot of the program dialog and the Impress Slide Show settings. You need to uncheck Change Slides by Clicking on background for QtShowRunner to work without skipping through your slides.
Here is the SourceForge page for the program.