I'm not sure what you mean by "import the library" - if you mean scan the drive and find music files, I don't think it will pick up the WAV files as they have no tag info. If your directory structure on the new PC w/ external drive is identical to your old PC, then you should be able to open a backup file of your library and everything would be there. If the directory structure is not identical, there are probably still ways to start in this manner and get all the files "reconnected".
I'm assuming you've already posted over on the JRiver forum for help. If not, you should - very helpful and knowledgeable.
I'm assuming you've already posted over on the JRiver forum for help. If not, you should - very helpful and knowledgeable.