Since we're building a Pathfinder RPG setting at bySwarm, I'd like to create custom data files in HeroLab for our new reaces, feats, etc. I am also creating a portfolio of sheets for NPCs in it. Is there anything in the license that prevents you from sharing these things as HeroLab files on your website?
No, you are encouraged to share your creations. The Pathfinder d20 SRD has a bunch of Hero Lab files posted that are discussed/developed prominently on the Lone Wolf boards.