This almost gave me a heart attack, but I figured it out:
- I configured and activated one of the custom user fields (extra_field_4) as a select.
- After that, the registration system got screwed up, users in list showing up as "/Registered" instead of "Shopper/Registered", couldn't manage account and so on.
- After I deleted the extra_field_4, the system was function correctly again.
I found the same problem here: http://forum.joomla.org/viewtopic.php?f=471&t=346576&p=1492698&hilit=shopper+group+default
It was reported in 1.1.2