If you lift one end of these 3 resistors, R15, R37 and R23 you'll have just the meter circuit operational, the tone and short led will be out of circuit starting with this might give you some idea where the issue is.
Check to make sure D3 and D4 are ok and in the right way around, check to see if the meter is still ok and not blown open, a mulitmeter on ohms will make it deflect, probably all the way.
That design looks very good, however there is one big drawback I see, the meter zero adjustment, its possible to adjust it so that you have zero ohms between the op amp and meter movement, this would risk blowing the movement, I suspect this has happened with yours.
A 22k inline with the zero pot is a good idea, this would limit the max current through the meter to about triple its rating for 100uA.