Will follow esmi’s protocol. Thought this might be a more general, theme-independent problem. For @ Andrew Bartel:
/*
Theme Name: Vertical Theme Child
Description: Child theme for Vertical Theme
Version: 1.0
Template: verticaltheme
*/
@import url("../verticaltheme/style.css");
Thanks for your comment and link.
I had run this script to try to take care of that potential problem:
http://interconnectit.com/124/search-and-replace-for-wordpress-databases/
Will try the Migrate DB Plugin.
Thanks, re-exporting and importing the table structured it correctly and produced no errors.
The locally hosted version of the site is still broken (can’t access anything beyond front-page content), but that seems to be a separate problem and will call for a different support thread..