Populating a form field from a recordset

I have my completed form and I have added a "Subject" text field. Easy enough as it is, it all works including formatting it with UEmail to dynamically add the subject entered into the email that submits the form. Great.

Now over to my DA record list. I currently have a link that appears in each record. It's an email link that when clicked opens the email and fills in the record ID and Name into the subject of the email. But we are doing away with the pop up email and replacing it with this new secure form.

How do I bind the "Subject" field in the FB form with the record ID they click on and still maintain validation for that field?
AND ignore that binding if someone simply goes to the contact form and puts in whatever they want into the Subject field?

So far, I can get the Subject field to populate using a link from the record. But it removes the "invalid" value currently in the field for validation.

Can this even be done? I have all extensions.

Thanks,
TroyD