A brand new zen cart 1.5.5a

When installing tableau, I get check marks on every item except for "Added CSS JS Loader Configuration", where instead I get an exclamation mark and a pink background. Manual inspection reveals that all queries in new_install.php appear to have succeeded.

After install, I activate tableau... but when I attempt the "configure" button, nothing happens. No config panel reveals itself. Likewise with the "details" button.

Chrome's tools/developer tells me "Uncaught TypeError: Object ... has no method 'fancybox'"

This despite the fact that fancybox/jquery.fancybox.js and jquery_fancybox.js are both installed in includes/javascript

This has got me baffled. I have searched this thread without result. I have removed and re-installed everything without result. I have installed the same tableau at a zen cart test site with an older zen cart version, and it works there == configure reveals a panel where I can enter configs.

Any helpful suggestions appreciated.