A couple of bugs occur after every registry cleaning:
1) the "Music" folder is no more associated to its icon, and I need have it restored with a manual operation
2) the "Music" text is no longer in the language I got Vista installed with (Italian, in my case). It rolls back to the "core" language, being it English.
Here is a screenshot of the bug:
This occurs each and every time I make a simple "complete" registry cleaning under Windows Vista 32-bit, with always the latest version of CCleaner 2 portable version. FYI, I did not try under other OSes.