[CCleaner Professional - how is it really different]

Says it does "Full Cleaning" - "Cleans the entire computer!"  So what does it clean that is not cleaned in the manual (non pro) version?

Says it does "Automatic Cleaning" - "Automatic background cleaning Disk space monitoring"  So again, what does that really mean and how is it different?

I have used CCleaner for years.  Was considering the Professional Edition, but really need to know more to make that decision.

[Registry Cleaner - wiped out two programs from Techsmith]

I use SnagIt and Camtasia Studio - both were wiped out by Registry Cleaner.  I had to reinstall both to get them to work.  Why might this have happened and how can I avoid it happening with other valid installed programs in the future.