open the bindings panel.
Window -> Bindings
you will see that there is a biding group for the interprimus recordset, and there is another binding group for the login form
the problem with the login failing is because you used the interprimus recordset binding group in the Authenticate user server behavior.
for the login to work properly, you need to use the bindings for the login form, this will pass the username and password you enter in the form to the authenticate user server behavior.
open the server behaviors panel, Window -> Server Behaviors,
On the Database tab, click the lightning bolt icon next to the value for the username, this opens the bindings panel. expand the Login Form binding group and select the username form element.
Repeat this for the password.
