Did you update to 5.3.6?

Providing you've searched & found where the files are saved, make a note of the location of that folder.

To add that folder to LW's library... click on Library tab > click on Add Files.

Browse for the folder with songs in it > highlight that folder > click on 'Add Files' in the dialog box.

Files should now be added to your library.

If you want those files to also be shared, add the files (or whole folder if you like) to the Public Shared list in the same way that you added files to your library.