Comment 3 for bug 1724482

I tried a bit to look at this.

Note that when you continue the previous question ('partman/continue'), the installer moves on to the timezone page. I think that's part of the issue - this page can't handle the dialog. Also the question name ('partman-efi/non_efi_system') isn't matched by the list of expected questions, but I didn't find out yet if that's a problem because I don't know atm how to solve the first bit.