I’ve just been on a thread about this same topic, and i have a couple of solutions: store the ROMs in the folder unzipped, or chech the permissions of the folder
(copied from my reply to other person with similar issue)
I don’t see why it should stop unzipping during launch, but have you tried unzipping the files before with WinRAR? it would mean the system wouldn’t need to do it for you, and saves loading times. Use this page to help reference the symbol meanings inside the zipped file:
I have found no difference effect on using Japanese, US or European ROMs on retropie, but i tend to stick to ROMs that have either nothing after them (best option) or [!] (confirmed good dump or something along those lines).
It could also be that the permissions are incorrect for the pi to unzip the file properly, so give that a check too.
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