Trying to get that setup working too, PIC18F14K50 and these:

Code:
INCLUDE "cdc_desc.bas"
INCLUDE "DT_INTS-18.bas"
INCLUDE "ReEnterPBP-18.bas" 
INCLUDE "SPWM_INT.bas"
INCLUDE "USB_ASM_Service.pbp"

ASM
;----[High Priority Interrupts]-------------------------
INT_LIST  macro     ; IntSource,          Label,  Type, ResetFlag?
        INT_Handler     INT0_INT,   _ButtonPressed,   PBP,  Yes
        INT_Handler   TMR1_INT,  SPWMhandler,  ASM,  yes
        INT_Handler     USB_INT,  _DoUSBSERVICE,   PBP,  yes
    endm
    INT_CREATE ; Creates the High Priority interrupt processor
ENDASM
However I'm having a hard time to get a smooth PWM output that is not perturbed by the DoUSBSERVICE routine... So far the best results I got is by inserting INT_DISABLE USB_INT / INT_ENABLE USB_INT into the SPWMhandler, however the output still flicker quite a bit. I also tried to turn USB_INT into a lower priority interrupt but that doesn't work (the PIC does crash).

Is there a particular solution to make them work together? any hint on this would be greatly appreciated.