Thanks everyone for your help and info. I was able to get Xcode and the CUDA plug-in. Next on the list is to try to and get one of the examples working from the SDK…
No I haven not been able to get a real build script going in XCode. I started to just use the terminal. I was able to compile, get the object files, but during linking from the command line I got duplicate object reference errors.
I was getting those too until I realized I was both including a C++ file and having Xcode compile it. IIRC unchecking it in the sources list (whatever that the checkbox at the right of each file is called) caused it to be only compiled once. I’m posting the project I got working to the Integration with Xcode thread.