I can't be the only person who has come very close to accidentally doing this.  So whenever i install a new item/char/hair/clothes etc, i goto the content library and right click ->"refresh".  the thing is that just right before it is the command to remove your runtime directory.   this is like putting a gun right next to a a candy/cookie jar.

anyways, something i found useful that might save others time.  when doing a "categorize" on items in the directories to organize your content, if you want to do sub-cats all in one click, you have to do it twice.  if you only do it once, only the directories get created and you end up with an empty directory.

I stay with Daz3.  NP with anything..