Are you talking about a separate Folder for the AI or the Multiple A/C in one folder trick? If the later, MB doesn't like that and it causes problems in DCG campaigns. I tried using the Alpha Sim B-25D/J package which is set up that same way and it crashed the missions at startup.
If you're talking about putting it in a separate folder that's no problem unless you try to fly a DCG Campaign with the Beaufighter. You can only have one A/C per formation.
I'm probably going to have to get someone involved that know a whole lot more about Airfiles than I do.
I will defiantly be uploading it as part of a Revised/Expanded BoBS Campaign and two back to back 6 month long PNG DCG Campaigns.
If you want to play with the parts and pieces I've put together, A/C.cfg, Airfile and DP just PM me with your e-mail addy.