Comcast DVR Cable Box 
Universal Remote URC-100 (Learning) w/IR blaster 
iMac CoreDuo 
SlingBox (w/Mac SlingPlayer beta) 
Logitech DiNovo bluetooth keyboard 
Remote Buddy

I watch TV on the Mac via streaming from the SlingBox using the SlingPlayer. 
I have trained the Universal Remote with all the Apple Remote codes, and it works great. I can control the iMac via Remote buddy just fine. The goal is to have the user experience be just like my old setup, where only the remote was necessary to interact with all devices and features of the home theater system. I prefer to use the Universal Remote to control the Comcast DVR via RF (using the on-screen SlingPlayer remote assumes mouse and or keyboard control) so it's easier to just cut out the SlingPlayer/Remote Buddy middle-men and just go directly to the cable box. what that means is that I just want to be able to launch SlingPlayer via Remote Buddy, but not have the IR remote send any other signals to the SlingPlayer behavior. Once the iMac is in full screen SlingPlayer mode I want the + and - buttons (mapped to vol up and vol down on the Universal Remote) to control the volume of the iMac at the OS level. Firstly because the volume control via the SlingPlayer behavior doesn;t seem to work, second because I like the feedback (big cross screen volume progress bar) that the OS/Front Row provides. My question is if there is a way to include SlingPlayer as a launchable app via Remote Buddy, but once it is launched immediatly pass volume control back to the OS, but keep SlingPlayer in the foregound. The closest I can get is removing SlingPlayer from the behavior list in the Remote Buddy prefs, but this forces SlingPlayer to the background with the result that the Dock and Apple Menu bar appear on top of the full screen TV picture (auto-hiding the Dock only solves half of this). So the problem is that if SlingPlayer is "captured" by Remote Buddy, the volume controls don't work, no matter how I remap them in the Remote Buddy prefs panel, and if I remove SlingPlayer from Remote Buddy, I can't full screen TV without the menu bar. And this needs to be transparent/automatic behavior when SlingPlayer launches - it is not acceptable to me or my partner that we manually change the behavior from SlingPlayer back to something that returns volume control back to the OS. Interestingly the volume slider on the Logitech keyboard does "talk" directly to the OS volume control, which tells me the OS can listen to some external devices even when SlingPlayer is in the foreground, but we do not want to watch TV with a keyboard.

Thanks for any help or feedback, 
Eric

if I understand you correctly, you want the plus and minus buttons on 
your Apple Remote mapped to system volume increase and decrease when 
SlingPlayer is the frontmost application.

That's easy to achieve:

1) Go to Preferences > Mapping > SlingPlayer 
2) Select the Increase Volume and Decrease Volume actions from the 
"Audio, CD & DVD" Behaviour for the respective entries of the Plus 
and Minus buttons in the table (including the "hold" versions if you 
want).

Those are the only changes needed in a stock install. Remote Buddy 
will then even display a huge, translucent volume bar.

Hope that helps.

Best regards, 
Felix