I would try making a dedicated print layout specifically for your PDF. That theme is not that great for printing and it would give you the opportunity to easily script a save/email PDF script. Filemaker has built in "print" themes that work best for print/pdf output.
Say you made a new layout called "record print", your script would be as easy as:
Go To Layout [ "record print" ]
Set Variable [ $file ; "file:" & get(temporarypath) & "attachment.pdf" ]
Save Records as PDF [ $file ; current record ]
Send Email [ put $file in the attachment setting field ]
Go To Layout [ original layout ]
Then tie that script to a button on your main layout, and you've got something that automates the entire process.
As for why your current layout is coming up blank, it looks like maybe something on your layout itself is set incorrectly. You can check the sliding options under the inspector, and also make sure that you're displaying that layout in form view. You might also want to check the body part settings to make sure it allows the part to break across pages.