Correct, this is the course Bill Foley co-purchased hence the Rock Creek name. There appears to be several people at Black Rock and at Rock Creek that think they will unite as one entity in the future, but my understanding is that there is some disagreement on how that will happen.
The elevation transitions were handled well. The biggest elevation change is on the par three 5th hole which is a pretty big drop. #3 plays uphill from the tee but working up that hill is no more extreme than what Augusta has. A very small gully is crossed from the 9th tee to the fairway as the course climbs uphill and begins the transition from open ground to the trees. The transition could be walked easily. There is a pretty good drop from the 10th tee to the fairway but nothing crazy. Overall, the property didn't feel extreme to me but some of that may be because I play a lot of mountain golf. I'm not sure whether the club requires carts or not, but other than the transition from #5 tee to #6 tee I didn't think it would be that bad of a walk.
The concept behind the double green on the 5th hole is that the player with honors from the previous hole gets to decide which green the group will be playing to. I thought it was an intriguing idea that certainly makes the hole more memorable as well as delivering increased variety.
Here is another photo (6th hole) where you can see some of the holes in the distance. Certainly running along the hillside but gaining/losing elevation at a manageable pace.