While in Lightroom 4 I selected to edit a raw image in CS4. I got the message that I should have Version 7 of ACR installed. The latest version for use with CS4 is version 5.7. As a result I am put directly into CS4 with no option to go to the raw processor. I am assuming that if I had Version 7 installed I would go directly to ACR processor.
No, you wouldn't. You'd still end up in CS4 proper, not ACR. ACR, in that case is run silently on your way to PS to interpret the changes you've made in Lightroom.
With the mismatch, you need to choose "Render in Lightroom" for your changes to make it into Photoshop.
Thank you Lee and Hal. Since sending my question I've done some testing and realize I'll just skip ACR and do my initial editing in Lightroom, and treat it as if it was done in ACR then do the rest in CS4 as before.