Might be silly, but did you clear your cache folder manually via FTP or just through the manager? May try flushing the sessions or clearing your browser cookies. Also, is it every page (System settings, dashboard, users, etc.) or just the dashboard?
It's usually a good idea to run an install after moving files. Without seeing the config file paths, it might be hard to find the problem. There are several lines, so it's quite possibly a typo or oversight. Just upload the "setup" folder and do an upgrade. Make sure to CHMOD your config.inc.php under core/config to be writable. Also, leave all the database stuff the same.
If this doesn't fix it, there's likely something a bit more important missing in the core & manager folders, which can happen if they do an install and find and replace (it doesn't always replace everything properly), which may necessitate a full install. If this is the case, be sure to make a backup of everything, especially your config files and your database, and upload everything but blank config files and run a setup again as an upgrade. This should clear up any problems.
If this doesn't work, try doing a full fresh install. Make sure the dashboard works after doing so. Then upload the various components and asset folders and import the MySQL. If it breaks it again, you can start debugging from there. It may help to not copy the components, and uninstall / force remove and re-download / install them.
The blank manager page happens to a lot of people, it's always just a small thing. Hope this helps
NOTE: Seriously, backup everything and create copied folders. You don't want to lose the config files or important components.
