I found a case where using Unarchiver v1.6 on a rar file of an iso disk caused Unarchiver to run forevvvvver, using about 70-85% system resources. I eventually Quit the program from Activity Monitor.

I tried the same rar file in UnRAR v2.2, and it ran through the extraction, up to 99 %, looked like it would finish, but then its status window reported a CRC error. and finished the process. The reported error statement from UnRAR: "CRC failed ??? - the file header is corrupt"

So I am guessing that Unarchiver 1.6 got hung on the CRC error and never quit. But why use up all the system resources in that? And no feedback in the Unarchiver other than a perpetual 'spinning' bar.

And I think it would be good if Unarchiver would give some sort of status indicator, both of progress and outcome (or failure).
(I looked in Console logs, did not see anything that looked like unarchiver)

Thank you. All the best.