I tried it both ways MPASM and PM, and both of them do not work. I cant even compile.

I even tried to compile this program:http://melabs.com/samples/LABXUSB-18F4550/USBMOUSE.htm

I can compile if I just use in the overhead: DEFINE OSC 20 and put an external 20mhz crystal, it is somewhat working, but is not keeping the timer properly and is not showing all the letter on the LCD.