I have Spartan running and have taken what I copied from Notepad to paste in the form and saved it as a txt file which I've attached so you can see it. As you can see there are no paragraphs in the Notepad version as well as some centering differences from the email. That's because once I pasted the letter's contents into the form I added the paragraphs back in and adjusted the centering to match the sender's original message as formatted in Word. But the formatting was done in the email form as it had been stripped out in Notepad. So that's why I don't think it was leftover junk from Word.
I tried saving my gmail copy of the message that was sent out to my Google Drive but gmail saves it as a pdf. I can forward it to you if you think that will help (I'll need an email address) or if you know of another way to attach it here.
I did add the style to the email template, but I'm not holding out a lot of hope on that as it's for the <p> formatting only and doesn't really address the extra characters.
So if you want me to send you the email, let me know how to do that. Otherwise I guess I'll just wait and report back the next time I use the form.