I've created a Generic Activity that allows me to see/hear the audio/visual running on my HP Desktop PC thru my Denon reciever and Sony TV and have assigned it to the name "Extend Computer". When I want a larger audience to see what's happening on the PC I simply hit "Extend Computer" and the content displays on my theater setup. I'm bummed to say I can't find the option to control the volumn via remote...typically every activity that uses my Denon reciever has volumn control via the remote however this Generic Activity doesn't allow it. Did I miss something during setup?

Go to "Customize" for the activity, then "Change behaviour of buttons"
Assign the volume butons to the receiver volume commands.

Generic activities don't automatically assign things like volume and channel buttons since it doesn't know what you're doing, that's why you have to do it manually as czzer suggested. You can also change the default mappings in other activities.

I kinda thought this is what they wanted me to do but it seems wierd to modify a device for a single activity considering the device works fine in numerous other activities. Thanks for the quick reply.

It's not the device at all - it's the activity. Each activity has it's own button configuration made up of buttons from all devices. Each device has it's own button config also but that's only used when you're in device mode.