Brent - You're in for a treat.
Regarding Betchworth, I could not tell which Colt holes were original, but there are some really nice ones. Others pretty straighforward. Wait until you see the view from the 4th tee. A signature hole, but not the finest on the course, IMO. A member there (a Yank as they say and also a very close personal friend of mine, too) told me about some tree removal required by the local government, since the trees were not "native" to the area. In fact, if you're looking for or need an extra for golf that day, feel free to drop me a private email and I'll pass it along. (He lives minutes from the course.)
Walton Heath is really a great place. I'll be looking forward to reading what you think about it.
Hope the weather is good!
-Best