Just to complete for others that will search this again.

If you installed and your Default setting was Nested, then Users registered after that will be Default Nested. If you change the Default to Flat, those previous Users will reamin at Nested in their profile and the New Users will be at Flat by Default.

Or so it seems to happenend on my sites. I think.

- that really helped. i would have never figured that out.

- cheers