controller function form validation

[eluser]Jan_1[/eluser]
[quote author="jzmwebdevelopement" date="1329245489"]
My Question is:
Show an error if the username is taken -> currently just submits as normal even through the specific user is in the database.[/quote]
Sorry, I don't know. May be its because of your Success-Check of users_model->createUser. Maybe have a try with a simple callback_function instead of is_unique. Maybe it's the model. I don't know.
[quote author="jzmwebdevelopement" date="1329245489"]
Populate with data if there was an error -> currently populates with the imported data if correct
[/quote]
What do you mean with imported data? Should be what was filled in the form fields, isn'it? And you reopen the form field directly after insert by the same function. If you do a redirect('createUser',refresh) you don't get filled form fields after correct insert.