We use digital signatures in our office and use images for the signaturelogo.pdf.
Now when I place a footer on it and save it I can get the date to appear, when I use a text field and try to update it at the document level it shows up fine when you look at the signaturelogo.pdf, but when you sign the document that part will not show up.
Makes no sense that a footer will work but not a text field. Can you add a text field to a footer?
This type of signature field not only signs the PDF for many legal purposes, but also locks specified fields. You can request that specified fields not be locked, but their modification will show that the PDF has been modified since it was signed.
Have you looked at the JavaSeript console for any errors?
George Kaiser