Prizm, you specifically mentioned keeping script values safe from users. You don't need a windows registry manipulation to do this. All you need is hash tables. In fact, that is one of the best reasons for using hash tables.
Having said that:
1) Ethics: script users should be able to tinker with the script values, or else you should not be able to set those values yourself.
2) Windows Registry Manipulation will open mIRC to another category of hacker. We all know this. I'm surprised no one has mentioned it on this thread.
3) Prizm, if you don't know how to work COM objects, how do you REALLY expect to know how to mess with the windows registry safely?