The admin user you set up when first setting up the xf board is converted to a normal user if the first user in the database is not an admin for the vb forum you are importing. (I am assuming as I didn't try it with the user as an admin)
As no other admin had been imported (failed on first page around 150 users imported) I had to edit the xf database to make my inital xf user an admin again, using http://xenforo.com/community/threads/promote-to-admin-via-database.12356/#post-163304
As no other admin had been imported (failed on first page around 150 users imported) I had to edit the xf database to make my inital xf user an admin again, using http://xenforo.com/community/threads/promote-to-admin-via-database.12356/#post-163304