Thanks for putting up the schematic !!!
One thing I notice - you do not have a diode in series with the +5V 7805 regulator input. If you power the board from USB, and have no voltage on the +12, the 7805 will not be very happy ( = it will blow out). A 1N4001 is perfectly adequate as protection.
One thing I notice - you do not have a diode in series with the +5V 7805 regulator input. If you power the board from USB, and have no voltage on the +12, the 7805 will not be very happy ( = it will blow out). A 1N4001 is perfectly adequate as protection.