I know, already answered on the other similar thread,
Are you a developer who uses NSIS to distribute your application? Are you a Winamp plug-in developer who wants to use NSIS to distribute your plug-in? Have suggestions for other people like you? This is the place.
However I'm wondering why one would like to deal with the registry by such an unsafe way while it is quite simple to do it with NSIS built-in instructions.