It's just like the IsGenuineEx() function. (The structure use, setting the size, and using the members of the structure).
Look in TurboActivate.h for the structure definition (it's at he top of the file).
ActivationRequestToFileEx() and ActivateEx() both allow you to pass extra data to the activation servers about that particular activation. If you just want regular old activations then use ActivationRequestToFile().
Does that make sense?