Re: 404 on Change Password
cyndy, go to the wpmu back end BuddyPress > General Settings and just Save Settings on that page after selecting the bp 1.0 member theme. bp might not be detecting the new member theme location. Upgrading to 1.0 means that the member theme is now located in /wp-content/bp-themes/bpmember
Give that a save there and see if the problem goes away.