Pre_Render & Pre_Validation issue, plus GFAPI create issue

Using the documentation and the setup as per this URL - gform_pre_render - Gravity Forms Documentation

I have setup a form that upon loading hides some fields. On the initial load of the page, the call back function works as intended. The callback function changes the visibility of some fields.

However, this doesn’t work if there is a validation issue.

The same occurs when I don’t have the filter applied. It seems that by default that if a field’s visibility is set to “Hidden”, it still shows on the page when the validation fails.

Any idea on how to bypass this?

I have also tried creating a field dynamically as per the documentation and this thread - How to create a set of fields dynamically on page load?
Essentially using this simple text field example.

The field creates as expected but when marked as isRequired, it shows the old style asterisk (*) instead of (Required)

Plus, upon submission it fails.

Some help would be great?