I am currently running Big Sur 11.4 on my iMac but the CCleaner window is showing Mac OS X 10.16 iMac 17.1, Quad-Core Intel Core i5 @ 3.30GHz, 32.0GB RAM.
I also tried to purchase the current CCleaner Pro and after the Product Key was issued the downloader stopped working. I can't figure out where to enter my Product Key to get the CCleaner Pro to work. Anyone have any ideas to help me out?