I have no idea how SFC3 works as I don't have it. It is intended to be a DN. I gave it the FBB UI for SFC2. So it has 8 heavy weapon slots and 6 light. total of 14. AS far as how may phasers and photons. Isn't that determined by how the player builds the ship?
Sorry I can't be of much help with SFC3.
Here is the UI I used if that helps.
btw I updated the zip file about 3 hours after I posted it. If you got it right away, be sure to redownload it. As I fixed a small mesh error and added a texture I forgot.