.............
How was it 'patched' any why? 3597's firmware doesn't have MSV presently so there's no need to patch with the
[Only registered and activated users can see links. Click Here To Register...]. It can simply use maps unlocked with latest gimgunlock.
..........................
Don't put the GCD file back, it's not needed anyway. Maybe the map on the card is faulty. Remove the microSD card if it's still in the device, then
flash the device with ORIGINAL (not patched and not cured) V5.50 firmware as an RGN in preboot and see if it boots. If it boots properly, turn it off and put the card back in to test.
Report back and don't worry as we have plenty more to try in steps if that doesn't work.
Don't forget to tell us in full detail what you did first before this happened.