[chris8204]

I asked the same question a few days ago. Here was their response:

The current version does not support the hand histories that are stored on you hard drive. They are of a different format than the ones fetched by email.

However, the next patch (version 1.50) will support the hard drive files. Among other things this patch will also let you overwrite any hand in PO by importing from a hand history from email or hard drive.