Hola Chrischris,
I am not conversant in C.
I am using the same file for both PICs except for the changes described above and the config. Chris
Most probably, at this stage, a good way of having a non working project. Keep it aside until you learn the differences. You could realize easily just by comparing the respective instruction sets. Could you?
Even if it looks excesive (which is not), those families made for different micros. The worst mistake you could do is to expect they are (almost) the same.
Maybe your difficulty lies in the correct configuration of the new micro. What I say could not help but, if you start with the minimum, that is, all peripherals disabled, you should be setting very few functions, pins, etc through the configuration.
Even if it means extra work, be patient, RTFM and try to just blink a LED. For the first test, try to use a port, if available, where the pins are not commited with other functions (not common anymore with current micros but worth to tray).
Points I would go straight
to check:
a) Oscillator settings. Recent 18F are much much more complex than before. Did not check yours but I suspect it has way too many options.
b) As posted by Max above,
that desired pins are set as digital. The most common trap in PIC micros, ever.
c) Use of the TRIS registers. (No idea how C deals with them).
And, please, before that GLCD, blink a LED; that is, blink a LED. Fight small battles and win the war.