Code protection does not (should not) prevent the device from being erased and when it's erased the code protection bits are erased. Besides, your config says CP_OFF so I would THINK the device is NOT actually code protected.

I see you're using internal oscillator and you have MCLR off, I wonder if this may be related to the issue in the other thread with the bricked 12F675 part.
Do you need to have MCLR off or can you possibly try another PIC with MCLR on and see if that makes it better?

What programmer are you using?

/Henrik.