Joe, you're correct. 18Xxxxx need MPASM or i will never compile anyway.

Let's open any 18Xxxx.INC in PBP folder..
Code:
        NOLIST
    ifdef PM_USED
        LIST
        "Error: PM does not support this device.  Use MPASM."
        NOLIST
    else
        LIST
        LIST p = 18F452, r = dec, w = -311, w = -230, f = inhx32
        INCLUDE "P18F452.INC"   ; MPASM  Header
        ;__CONFIG    _CONFIG1H, _OSCS_OFF_1H & _XT_OSC_1H
        ;__CONFIG    _CONFIG2H, _WDT_ON_2H & _WDTPS_128_2H
        ;__CONFIG    _CONFIG4L, _LVP_OFF_4L
        NOLIST
    endif
If you don't select MPASM, it will show you that message.

At very least, this is one reason why i don't use PM, always MPASM. Kinda annoying stuff to switch everytime between one and the other.