I tried upgrading from 1.5 last year, but don't recall the failure issue. Just attempted a fresh 1.6 install, ran update.php, and got a Fatal Error. See image.
Anyone? This is outside my scope.
You don't run update.php on a fresh install. It is only run when a version's code files have been replaced by those of a new version when performing an update/upgrade.
Well, I logged out of everything, ran the update routine again... success!
But I'm still getting the "Deprecated" messages. See https://forum.coppermine-gallery.net/index.php/topic,80746.0.html