As long as you copied all the files in the Calibre library including the metadata.db file then you should not have to re-enter any data - simply pointing Calibre at the new location should do the trick.
You might want to check that you have full read-write access to all the folders and files at the new location. If that is not the case it might explain your symptoms.
If you want to have 2 separate libraries, then you do not need two instances of Calibre installed (and I also doubt it would work anyway). The answer is to have two shortcuts for launching Calibre and pass in the location of the library to use with each shortcut using the
Code:
--with-library library_full_path
runtime parameter at the end of the command used to launch Calibre.