Can I specify a different filename for the images when running Automator?
No, not currently. When Barcode Producer creates a batch of barcode image files with the Automator Plug-In, the resulting files will be named for the barcode value encoded. If you want to batch change the file names, a 3rd-party file renaming utility - such as this one - would be the best bet.
Barcode Producer for Mac/PC creates perfect barcodes for retail packages, labels, books, packages, and everything else.