Les,
Actually, the stuff behind the password-protected area isn't really what you need. The general software is under downloads-software updates. Then click on I Agree at the bottom, and off you go.
It is true that there is a significant learning curve associated with programming crestron systems, yet if you start with Application Builder you can have it generate a SIMPL program which you can analyze and reverse engineer. Of course, you could always have someone else do the initial program for you and then revise it yourself.
As for the 2-way capabilities, you are correct in your assertion that the ST-CP/ST-1550 combo only allows for 1 way communication. For 2 way communications you would need either the STX-1550C or the STX-1700C (The 1700 is the newer model with an Isys graphics engine), the STRFGWX 2-way antenna and a processor (The ST-CP would work but it is fairly limited, so a CP2 would probably work better if controlling a casablanca).
If you have any other questions, feel free to ask!
BL