I have "unlinked" my last attempt in FTM 2012 at downloading my AMT.
And continue to work solely on my AMT (Ancestry Member Tree : online).
When I notice that FTM 2012 has received an UPDATE, and the version number has moved on, I will give it another try.
The current (flawed) version of my FTM 2012 is 18.104.22.1688.
Until then, no point persisting with FTM 2012 and its TreeSync feature, as Ancestry has acknowledged that it has a bug, and for larger trees with many media images like mine, the update is needed to overcome the problems.