I've begun writing the GUI for our pilot test, and I have two XML files happily loading and being displayed, and xml:id attributes being added to all the target elements (a requirement for the subsequent processing). Now I've started trying to figure out how to run the NCD process externally and get back its return value. The problem is that the return value is a float, and in Windows it seems to be impossible to get anything back from an external process except an integer (with GetExitCodeProcess). Presumably NCD is writing to StdOut. I did find this site which suggests a possible solution, which I'll look at tomorrow.