i agree with robert , check port A config as a start point , as port a 0-5 are analog optional , also when connecting port at 64mhz i had some very bad results when not using the "LATA.x" commands for outputs , here Port A for the 18F67K22 , should be much the same

Code:
' -------   Setup port A Variables  & directions  ----------
    ANCON0.0 = 1               ' Set PortA:0 Analog / Digital allocation - 0 = digital ,1 analog - ANSEL0
    ANCON0.1 = 1               ' Set PortA:1 Analog / Digital allocation - 0 = digital ,1 analog - ANSEL1
    ANCON0.2 = 1               ' Set PortA:2 Analog / Digital allocation - 0 = digital ,1 analog - ANSEL2
    ANCON0.3 = 1               ' Set PortA:3 Analog / Digital allocation - 0 = digital ,1 analog - ANSEL3
    ANCON0.4 = 1               ' Set PortA:5 Analog / Digital allocation - 0 = digital ,1 analog - ANSEL4 Set RA5 (AN4/ ANSEL4) to be analog input for V-Mon 
        
    TRISA =  %00101111         ' setup Port A input=1,output=0 for I/O pins , set input for RA0-RA3, RA5  
    PORTA  = %00101111         ' Clear Outputs