Hi there @canadaduane , great question!
Have you seen this post:
this should help you dig in and see if the lib you're trying to use will work in the Spark Core context.
Regarding wire.h + wire.cpp, you definitely don't want to include that, those include platform dependent elements not designed for the micro-controller on the Spark Core. Working "Wire" functions are available within your firmware without including anything and are documented on our core firmware reference docs: