Jason, Huge thanks.
For those of you viewing this thread, my problem was with the DW ../../ shorthand and the fact that UE needs precise source location (i.e., www.....). I kinda figured it out, but Jason's explanation made it clear. UE acts just like an email client. It can't interpret ../.
So when I was revising my template in DW, I had to manually enter the full directory address in place of the automatic ../.
Simple to do, but the key to my issue.
Good luck campers