Whoops! Somehow the menu-data.sql script was built without the following entry:
REPLACE INTO `mnu_account` (`rdcaccount_id`, `account_name`, `rdcversion`, `created_date`, `created_user`, `revised_date`, `revised_user`)
VALUES(1, 'Shared Account', 1, '2007-09-13 11:41:52', 'AJM', NULL, NULL);
This should create the 'shared' account with the id of 1, with all new records having a id greater than 1.
Empty your version of mnu_account, run this sql statement to create the first record, then you can create any new accounts.
I shall update my sql scripts for the next release.