I've been using Notepad++ for a couple of weeks and only recently have I found out how to delete/modify macros (Settings> Shortcut Mapper> macros begin at around 70). The only reason I actually came to this conclusion was from this site:

http://www.seancolombo.com/?p=29

I love N++ but the macro management needs a revamp. There should be a way to do it from the macro menu, excluding all the other shortcuts. That would have saved me a whole lot of frustration.