I'll try help you here:
1 - Have a read of this Bookpedia Help file: Importing entries
2 - If you're running version 2 of DL, you'll have to export your data to 'Delicious Library 1.5' format first by going into the File menu and choosing Export > Export to DL 1.5. (The file format of DL2 is closed and the Pedias cannot access it for import.)
3 - Then use the import command in Bookpedia and CDpedia to import the "Library Media Data.xml" file into the program. You will find this file in your Home folder under ~/Library/Application Support/Delicious Library/
4 - The cover images will automatically be included in the import and the programs will know which entries are books and CDs so they'll automatically import the appropriate items.
As to your second question, have a read of this
Help document: The different collectionsSo basically you have your Main Library, just like the Main Town Library building and then within that Library building you have different Collections and Sub-Collections.
How you display your Collections is explained here:
The different view optionsHope this helps
