I created a form containing a button that uses the event.target.buttonSetIcon() method to add a mugshot to the file. Strangely, when I submit the file, the button goes blank. The only way I found for the icon to stick is to add a signature field that "locks" all field before submitting. Is it normal?
How, and what, are you submitting, exactly?
Well by submitting I mean once I distribute a file manually (tools/forms/distribute) and want to collect forms that are submitted by the person who fills the form. What is submitted by default is a .fdf I think...
I don't think that the image data is included in an FDF. You should have them submit the entire PDF file.