If you don't change the skill levels and just give yourself the extra 10 skill points, do you still get the error?
In Vista, try running the save editor as administrator (right click program/shortcut).
If that doesn't help, try copying the save folder (or just the data.000 file) to another location to edit from. The program was released before Vista was out, so maybe it has a problem with how Vista relocates the savegame folders, or the length of the 'users' path, or something.
Ran as administrator and it saved with no error message. Didn't have to move the file or change the path, either. Will now reditribute skill points and load the game...
