Our Dedicated Server runs several copies of PP and Listings Manager, and we've just completed a migration to a new Server using Plesk's migration process which effectively mirrors everything over so no reinstallation is required.
Whilst LM is working fine, calling up the PP Admin login gives brings you to the Installation process.
The one major factor is that on the old server the file paths were /home/httpd/vhosts/domain/..., the new server is /var/www/vhosts/doamin/...
So, having taken safe copies of the files, I directly edited setup.dat.cgi & page.dat in cgi-bin/publisher/data to change all the paths.
But still getting the same problem.