[Bongle]

Generally, that means you don't have your include directories set up properly. So the compiler is looking for these files that you have #included, but cannot find them. Since I don't have MPLAB in front of me, I can't give you exact instructions, but here goes:

Somewhere in the 'project' menu (or a menu similar to 'project'), there should be an option to set up the compiler or linker, or to set include directories. Once you find that menu, you have to input whereever you put kevin watson code that has 'encoder.h' and 'gyro.h'.