You want to add the radio skin to the ONSTART command in the exectbl.ini.
Pre-loading the GMPC skin will fix your other issue.
The way it currently works is.. when I open RR to the menu.skin, the radio doesn't come on, I have to go to the radio_player.skin first. Also, I want Garmin Mobile PC to start up in the background and get past its splash screen so when I open the GPS skin, GMPC is already there. I tried to preload radio_player.skin, but that doesn't start the radio. Maybe I'm not doing it right.
I'm using my own skin which includes Monkeyracer/ElCamino/Thunderstick's GMPC overlay and OSK and MitchJS's cable and Visteon for the radio.
That only works if the resume.ini file gets written.
That raises a question (to myself, I guess) as to how I ultimately plan to implement this sytem. For now I am developing the software on a laptop (which doesn't always even have the HD radio cord plugged in) while I assemble the hardware that will eventually end up going into the truck. I almost always exit RR, then cold start it when I get going again. If the standard method of shutting down and starting up is to hibernate and resume, then I may be trying to solve problems with my software that won't be a problem once I permanently install the system.
I appreciate the help so far. It sounds like I may have missed some upgrades to RR that will help.