As users of the beta software, which I think has been made official already, are already aware, you can't use the old methods to add upgrades to your Slingbox.
I have been given the new procedure by the guys at Sling. You can still create your binary upgrade files just like you used to, but what you can't do is update the SBAV.cfg file so that it recognizes them. Instead, what you need to do is manually access the new code.
To do that, you start going through the normal procedure to activate a new code, but at the end of the process you select "other" and then you select the code that you created from the list.
For example, if you created a new binary file for your DirecTV box and you called it S1234_PL.bin, to activate it, you would select SAT > DirecTV > Other and then select S1234 from the list that pops up.
The reason you would select "DirecTV" before selecting "Other" is so that you use the DirecTV "skin".
As you can no longer edit the SBAV.cfg file, if you want to see the layout of the various "skins", here is an archived copy of the SBAV.cfg file...
https://www.hifi-remote.com/forums/dload ... le_id=2584