We also used RimRock last year when we did Ruby~~~> Westwater. No complaints. I think they may charge a fee to use their launch. Last year we got a camp site the night before our put-in date at James M Robb State park, Fruita section. Its a few mins drive to RimRock to drop off truck for shuttle. We left one car at the state park. I believe you can see the RimRock launch from the launch at the state park.
And yes we had to stop at the Loma Put-in to check in with the ranger/permit...
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