[firstimecaller]

in the userCP template responsible for making the menu on the left side (I don't know which off the top of my head) I added a conditional that checked the usergroup (you can find out how to do that here somewhere, it is trivial) and added an element in that to display the link to the extra profile fields edit/update page. On that page, you can also add a check for that usergroup, and deny access unless they have permission, but I didn't bother in my application.