I think that I may have come up with a solution for my issue with custom signup fields using BuddyPress 1.2.1 on a standalone installation of WordPress 2.9.2. After much digging around I basically ended up with a function that looks a little like the one below in my bp-custom.php file.
I too have also tried to use the tutorial that carrotcreative has mentioned, but not managed to get it working. The reason for my problem though I believe is that I am trying to use BuddyPress 1.2.1 on a standalone installation of WordPress 2.9.2. The tutorial is referencing the hook “bp_core_activate_account” which as far as I can see is in turn calling the function “wpmu_activate_signup” which I am guessing doesn’t exist outside of MU.
I’ve tried using the “user_register” too hook onto and run the “update_usermeta” ,but that doesn’t appear to be working. Does anyone know what hook should be used for standalone WordPress in the absence of “bp_core_activate_account”