Re: /members/ going to blank pages
Is wpmu 2.7 out now? Your site says its running “WordPress 2.7” not “WordPress 2.7-RC1-xxxx” like everyone else. The site in your profile must not be the site you are talking about.
Anyway, the dreaded “white screen of death” probably means you have some errors and it’s just not showing you them. Check your php and apache error logs and report back.
Sounds like the bp member theme is crashing for some reason. Do you have *all* the bp components installed?