Ldap attribute for Filr name

Hello,
Just installed a small Filr installation. Using Edirectory. Originally used emailAddress for Filr name. The imported user id ended up a 7#user@ourdomain.com .
Should I have used another item for email address to avoid the 7# at the beginning of the email address and hence the username? Also if I wanted to change the attribute to uid would I have to purge all users and their workspaces and do a re-sync after changing to uid?
Thanks,
Tom