Regarding first point:
I just want to disbale the "add me" button, after clicking on e-mail button. But I dont really know, if there is already a function to disable it.
I did find a workaround regarding the issue with "subject" and "attachement".
If you change the Text of the Subject to "Scanned from a Xerox Multifunction Printer" the two variables (subject and attachment) are match. After that, its possible to change the text of subject, and than it also will change the text of the attachement.