Hi Andreas, when I had a local repository, installed in k:\rpm.local, I had in @unixroot\etc\yum\repos.d,
[local]
name=My local repo
baseurl=file:k%3A/rpm.local
enabled=1
Personally, I've left most of my installed packages as i686, just converting to P4 as needed or as updating a package. Works fine as they're all basically the same architecture. The important thing is to update your platform to P4.