Probably no real need for the zip file, at least for the initial PowerON/PowerOFF Profile. Just look through for the tasks. It's super easy. I just configured my profile to SDBs configuration in less than 20 minutes. The only thing I got tripped up on was I accidentally had PowerOFF as it's own task, so it was running independently of the PowerON series of tasks. As a result, I never lost audio =p ... easily adjustable though.
I downloaded the Media Keys app, but I only seem to have buttons for Pause/Play, Stop, etc. I don't seem to see anything in that app for a volume bar. You stated in one of your videos that someone had recommended a "floating" volume bar that was always readily available. Did you ever find out what that was?
Also, do you happen to know if setting "Toggle Pause" doesn't work for the Google Music Player? It seems that powering off the tablet turns the music off without an issue, but powering the tablet on doesn't seem to realize that I had once paused something via the Google Music Player... I haven't tested this yet with Apollo or PlayerPro.
A 128GB micro SD card would solve all of my issues (80GB music library here), but alas, I don't think those exist yet. #firstworldproblems.