Occasionally my GoG.com Downloader seems to stop downloading things despite not being paused and having things partially downloaded.

Is this a common problem, is there a fix or is it being worked on presently?

I was searching for relevant topics but topics named "GoG Downloader" are not rare in the slightest so I figured I'd just make a new one, hope that's okay.

Yeah, sometimes mine stops too. My desktop is an old P-4, and it seems to usually stop when it's finished one game, and is starting the add-ons, or another game, and the merging of the one that just completed seems to be about all that old P-4 can stand at once I think.

Anyway, I can't help you with a fix or a workaround, but I can confirm it happens to me too. Although I will say, even with the "stops" it's still faster than downloading through my browser.