If you go to Tools > Batch Importer in Pro, you'll see a Sales Manager Business Edition option. Select it and click on 'Next'. The next page you'll be able to browse and choose your file, and continue on with importing your inventory to Pro.
SMBE ran off an inventory system and Pro runs off a batch system. Pro does contain inventory but to get your BE files into Pro, you have to do the Batch Importer. You can then put them in Pro inventory if you like, or keep them as batches.