While I was testing the prototype board with a 12F675 chip, touching with the multimeter probe the pin#4 (MCLR and GP3 input) the chip did a reset.

My configuration is set for internal MCLR and Input on GP3.

Code:
#config
    __CONFIG _INTRC_OSC_NOCLKOUT & _WDT_ON & _PWRTE_ON & _MCLRE_OFF & _BODEN_ON & _CP_ON 
#endconfig

DEFINE OSC 4
DEFINE OSCCAL_1K 1 	'Read OscCal value from the last location

GPIO=0
TRISIO = %00011000
Tried then to have MCLR on the pin and it clearly worked as a MCLR pin.
Code:
#config
    __CONFIG _INTRC_OSC_NOCLKOUT & _WDT_ON & _PWRTE_ON & _MCLRE_ON & _BODEN_ON & _CP_ON 
#endconfig
Then again set MCLR to internal and while it seems to be an input pin, it also does a reset sporadically. I'll do connect a resistor to +Vdd but wonder why this happens.

Ioannis