I even managed to set up ikiwiki so it works fine with git; but how on earth do I log in as an administrator? In the .setup file the admin user is set to 'zimek' but when I go and register 'zimek' on the web it appears as normal user not the administrator. What am I missing?

That's really all there is to it. The automatic setup script registers the admin user for you before the wiki goes live. If you didn't use it, registering the right account name will get you the admin account.

The name is case sensative, perhaps you really spelled one of them Zimek?

Or maybe you're the admin, and don't know it? Everything looks the same for the admin, except they can edit even locked pages, and can access the websetup interface from their Preferences page, if you have that plugin enabled. --Joey

Maybe I'm indeed. I know that I've disabled all the plugins while installing ikiwiki. Checking it now

Yup, I'm the God of my ikiwiki. (Thanks)