I presume you're referring to the fact that the Save button in the New Register dialog, does nothing (BTW, in the future I suggest you provide precise instructions on how to recreate, i.e. press Log In button, then press Register button, enter details and press Save).
This is a classic example where you should use the Trace function to visually debug what happens when Save is pressed - see http://www.tersus.com/#Tag=Trace for details.
If you do the trace, you'll find that the Commit Add User to DB service process does not start, because the Assign Roles Table mandatory trigger is not activated, as it receives nothing from the Assign Roles Grid data display data element, and this in turn occurs because it is not marked as a reference to an actual display (compare its black frame to the blue one of the New Register dialog above it, which means the latter is a reference).
Converting the Assign Roles Grid element to a reference is easy: Right-click it and select Parent from the type sub-menu.Alas, doing so will not resolve the problem in this case, since the actual display, to which this element refers, does not exist on screen (if you validate the model, you'll get an Invalid Reference warning to the effect),
I guess you tried to base your Register process on the Admin's Add User process, but note that in the Add User dialog, there is an Assign Roles Grid whereas in the New Register dialog, there isn't which makes sense, since you wouldn't want to allow a user to assign roles for himself. It seems to me you would want to provide a default Role (or Roles) for users, by changing the process - for instance change register's version of Commit Add User to DB (watch out for reused processes, such as Perform Action, in which changes will have an effect elsewhere as well) so that it does not expect Roles to be provided via the Assign Roles Table trigger, but rather include the logic specifying the default roles (at a minimum you'll need to assign the User role which must exist).;
I hope this info allows you to carry on.
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