[PROBLEM] CEC (new to this..)

[raspberry_pd]

Unfortunately I can't vouch for whether the Harmony and CEC will work together. The Pulse-Eight reference was as much to give you an idea of what is possible with CEC and an indication that it's an imperfect system since no manufacturer supports it completely. Nonetheless it can still work very well. I'd just give it a try. AFAIK there is no way that you can break anything by doing so.

To test which button events are being passed through, you can enable Debugging in the XBMC System settings (don't have them in front of me right now so I cannot give you an exact reference). Once you enable this, SSH into your Raspi and run a tail on the xbmc.log file. Using the -f option, you can see which button events produce a response in the log file as "CecLogMessage" lines will display. If your projector does not send a button event through to the Raspi, you won't see any change in the log file.

Good luck, keep posting in here if you have any issues. Your next step might be remapping some button events relayed by CEC and I can help you with that too.