I just did a fresh install of SW 2018 SP5 because the program had gotten so sluggish I figured 4 years of upgrades without clean installs had made a mess of the program files.
The fresh install did the trick and the program was starting in under a minute (5-10mins before) and toolbox (on local ssd) was loading instantly (3-5mins before), and some little bugs had been fixed.
After using SW for the day I ran CCleaner and it found ~500 registry entries it wanted to delete. I backed up the registry and ran the cleaner, and the next time I opened SolidWorks it was back to the same awful performance as before I did the fresh install.
Has anyone experienced this with CCleaner before?