it is very easy to overload a chip when bending. always use a resistor inline with your probes when looking for a bend, dont just use a wire to attach two points. its easy to silently burn out a black blob or other IC by accidentally sending too much voltage through an unsuspecting pin. standard proceedure dictates, when modifying a device only ever use batteries. once running on batteries, with the case open and board exposed, moisten the tips of your fingers and touch various points. the moisture will help conduct, and your body will provide 'some' resistance (and capacitance, we are afterall bags of salty water). this way you can probe for good bends and not blow the thing out in the process.
but remember, after you find your bends, even stable bends, you still need to watchout. don't directly connect two points without some resistance unless you 1.) know full well the bend is stable 2.) you don't mind burning out the device!
sam