Reply tracking needs to be configured within every Gmail account that Outfunnel emails may be sent from.
Copy the unique forwarding email address
Under "Forwarding" select "Add a forwarding address"
Paste in the unique forwarding email address that you copied from Step #2
Select the option "Forward incoming mail to - forward.####@outfunnelmail.com"
Make sure that "Keep Company Mail copy in the inbox" is selected
Save changes