[psy_wombats]

I don't think you should abandon Kevin's code yet, it really is very handy. However, bulky code that works is better than elegant code that doesn't. I'd save this as a last attempt.

What version of MPLAB are you using? There might a problem there, try reinstalling with 8.0+ or something. (I don't know MPLAB well either, just a thought.) And looking at the build stuff again... Do you have the include search path at C:\mcc18-3.10\h or similar? That's set by right clicking the project, (.mcp), selecting Build Options and using the Directories tab.