First off, make sure your portalalias table is set up correctly (for the new address)
Secondly, make sure the the dnn.config file is in the Install directory (so that it is not trying to install)
I did not try to do a DB restore, but I did have it build on my hosting environment and it was fine.
I also know that some files did not get FTP'ed up to my provider the first time around. Those are all things I ran into.
I recommend this if you have the resource to do it (as a test).
1. Create a new database on your ISP.
2. Point Web.config to this new db using the proper credentials.
3. Remove or rename the dnn.config file from the install directory.
4. Visit the URL (which will issue an install)
See if you can get the 'default' site up first...to make sure the code is all there.
Good Luck!