Here is the information from the manual regarding the recommended clearance:

"18. If you install the apparatus in a built-in installation, such as a bookcase or rack, ensure that there is adequate ventilation. Leave 20 cm (8") of free space at the top and sides and 10 cm (4") at the rear. The rear edge of the shelf or board above the apparatus shall be set 10 cm (4") away from the rear panel or wall, creating a flue-like gap for warm air to escape."

The 12v trigger issue has been a pain. I assume that Onkyo figured that all would use the receiver's amps for the mains and a separate amp for the 2nd zone. This has been a rather perplexing problem and tried numerous solutions. Turning on the 2nd zone and trying to get the Outlaw triggered by the Onkyo that way was simply not desireable. It was late, but appeared that my rear surrounds were not being fed with that setup as when I did a test tone I did not get a tone from the rear surrounds. My late night reading of the manual appeared to me to indicate that with that arrangement I could use 7.1 for the main system. Possibly, they intended to have 7.1 with the receiver amps and not through the pre-outs. Kind of a bummer, but I have a spare 950 lying around and it triggers the 770 very well (obviously). Kind of a high tech trigger device but a lot less hassle than my alternatives (also, no additional cash outlay). Gonk put me onto a potential solution involving a Belkin PF60, but the discount place was out of stock, and this works for me. I envision using this only until Outlaw comes out with their new pre-pro with HDMI 1.3s and TrueHD and DTS-HD MA abilities next year (assuming that happens). This is a good interim solution for me and allows me to listen to the new formats with an excellent unit acting as a pre-pro through a much better amp than comes with the receiver (I have not used the receiver's amps but cannot imagine them comparing to the 770).

Hope that helps!

Mike