Thanks John, I've followed your suggestion, and now the email arrives with the correct email header (paolo@clikka.com) specified in the collectedinfomail.tpl:
The following step would be to find a way to modify the lines above of the collectedinfomail.tpl to read the email inserted from the user while compiling the form (in the form field "Email_sender") and to have it directly transferred in the Email Headers "FROM:" replacing the "static" value paolo@clikka.com.
If I have an email address (email_sender) in the form data then I use it. If not, I pick up the default one from the InformationCollectionSettings block.
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