gonk: Look at what Roku has done with the HD1000, a.k.a. Photobridge. They've opened it up quite a bit despite being constrained by the very types of license agreements you describe. I should know: I used to work for the company that provided them with the Xilleon X225 (or was it the 220?) on which the HD1000 is based, and was quite familiar with it's capabilties.

I do think that a basic architectural/block diagram of signal flow and processing would be a good start, together with the type of technical information like RS-232 command/status protocol. An appendix to the manual, perhaps available for a small fee, with a signed acknowledgement that Outlaw provides no guaranteed support for the information within, would be a great start.