You can go to your incomplete folder (the path to it, is in the Settings).
Then copy that folder (don't delete it till safely passed on) and upload it to your new computer, and place it on an easily found path.
After that, install the latest Shareaza from the OFFICIAL site: Shareaza - Bringing P2P Together
If you've done that, make sure the setting in the new Shareaza links to the path you've got on your new computer. Apply that and restart Shareaza.

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