I've created a small tutorial for those who want to create a Joomla Registration form and need to store the value of some fields or hidden fields in an external DB. (Or need to change those value with PHP code before storing to external DB).
You can read the tutotrial here
Thanks, I've linked to your article from a FAQ here.
ChronoForms technical support
If you'd like to buy me a coffee or two, thank you very much
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