5906v Activation input on a Ram C/V

I've never done this. I offer it as food-for-thought.

Program the 5906 for 2-pulse activation on the wht/blu activation wire.

Connect activation wire to LOCK motor or signal in Caravan. Use relay to invert trigger if necessary.

2X lock activates RS. 2X lock again deactivates RS. Vehicle remains locked. IF the caravan RKE functions with a running engine (some vehicles don't) this would allow you to stop and start with the LOCK fob button, and unlock to get in it while it is running on RS. If you lock the Caravan with the fob, you can only push the button once.

EDIT: I read your post again. I don't fully understand "I can RS it with the remote, but once running I can't shut it down with LOCK". So you already have it connected to the LOCKs? And once it's running the factory fob doesn't control the locks any more? Many cars function this way. I don't know what the work around is, other than a stand-alone fob for the RS.