Not come across this myself chaps, but if its of any help,
Can you access your database in PHPmyadmin, and check that the relevant table is still in place is populated with your pilot data (table name is phpvms_users I think from memory?).
Secondly if you enable error reporting in your local.config.php your pilot list may give you an error explaining why the list isn't begin shown, possible coding oversight, or DB issue.
This is how i setup my development config, just uncomment the bottom two rows and add a comment to the top two, then switch back once you've finished debugging.
# Debug Mode is off by default
Config::Set('DEBUG_MODE', FALSE);
Config::Set('ERROR_LEVEL', E_ALL ^ E_NOTICE);
//Config::Set('DEBUG_MODE', TRUE);
//Config::Set('ERROR_LEVEL', E_ALL);
With more information on the exact nature of the problem I'm sure a fix can be found,