Thanks for the replies. I had in fact set up a database before the first attempt at installing MT, but, uh, did it badly. So I started from scratch, made a couple more mistakes, and painfully solved them. Now the blog has been recreated, the old entries have been imported, and things seem to be working well enough. I changed the name servers for the site, so the new blog should be online soon.
I do have a question about a weird result. As I login at the new blog's MT control panel, the pages are all...style-less. Just plain vanilla text. Imagine a CSS page without the stylesheet, and you'll get the picture. The control panel site certainly works, but its appearance troubles me. Has this happened to anyone else? Could I have overlooked a file during the MT installation, or perhaps corrupted it?
PS - It must be the files in static files folder: the docs and images folders and the styles.css file. They're all there where they should be, and I took care to send images as binary and other files as ASCII. Could permissions be the problem?