A partial solution with heartfelt thanks to "An English Gentleman"

This message:
1146 Table 'xxxxxxxx_zc1.xxxxxxxx_db_cache' doesn't exist
in:
[db_cache table]
was caused by a snarl up in the portion of

public_html/admin/includes/configure.php
which defines the db connection.

I have been down for a week & would never have found this in a million years by myself.