Looks like we're getting a good turn-out for this GB now. Have we got a list of everyone taking part? Welcome to the fun Audiophile121.
Resin is a two part material (a resin and a hardener are mixed together). Resin molding doesn't have the limitations that injection molded plastic has (like mold seperation lines and ejector pin marks). It is also alot easier to tool up for, you don't need the machined metal molds that are needed for IMP (you can even make your own molds and use store bought resin to mold parts). Parts usually come on pour stubs which can be cut-off.
Like armorman said, Black box is just a company that makes resin parts. There are numerous aftermarket manufacturers like Aires, True details and Jaguar. BB and TD cockpits are usually all resin, but Aires are mostly resin with Photo-etch details.
Resin pits are designed to simply replace a kits cockpit, but it never works out that way. You always need to do alot of sanding and test fitting. Normal plastic cement won't work on resin, CA (super) glue works best.
I think all of this info is correct, someone tell me if I'm wrong.