The MPLAB simulator for the PIC14000 has an interesting oddity, and I wonder
if someone who has a 14000 pod for the PICMaster can check if the real
hardware behaves the same way.

If bit 6 of the status register is set (this is RP1) then all data
memory becomes inaccessible, including the status register itself! It is
not even possible to reset RP1 to get out of this state (except by
resetting the chip or resetting the bit manually from within MPLAB).

TIA, Clyde