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This may be a dumb question. Did you test unzipping the games instead of leaving them .7z? Maybe it does like 7z. Just an idea. Good luck.
[2019-11-30 19:23:48] [INFO] [CollectionInfoBuilder] Scanning directory "C:\RetroFE\collections\ColecoVision\roms"[2019-11-30 19:23:48] [INFO] [CollectionInfoBuilder] Could not read directory