That first bit seems to say you tried to attach some pdfs and they can't be found. I can't help there other than to suggest delete and try again. 

To do the election on E, you should only enter a number (like 1 or 83 or ....) in the "Rental real estate enterprise ... harbor . That SHOULD generate the election. There is no signature required. Also put a 1 in the very last box to denote Business is QBI. Go to check return > Forms and toward the bottom SHOULD be QBI Rental ... Harbor election.