An addenda to my previous message. I deleted the Ancestry tree, deleted the FTM 2014 tree and closed FTM 2014.
THEN, I opened FTM 2014 as adminstrator, tried the same conversion routine with the same file as before and this time it completed. The 2 files are linked and media has uploaded. At this point I've backed it up and closed FTM 2014 for the night.
Vista 32-bit Home Premium
FTM build 18.104.22.168