JimT wrote:

But really is goes all over the place depending how fast or slow i rotate...

🙂 Yes, that's normal. When you spin the rotor manually, the motor turns into a generator and the generated voltage will throw off the multimeter. You're not supposed to spin the rotor but "reposition" it, ie turn it slowly and gradually in steps of 45 degrees or so.
Anyway, that's just an info for the future. Apparently your motor is fine since an external power supply can drive the whole mechanism without problem.
60 ohms seem still high to me, but maybe this motor is designed as low current, low torque model.

JimT wrote:

upon pressing " < " : P1-2 = 2.8V, P1-1 = 0.48V

upon pressing " > " : P1-2 = 0.48V, P1-1 = 7.7V

[...] Now the strange thing is that now i measure 3.34V from pin 22 of IC1 to GND and 5.16 from 21 to GND. 😂

The components that have been replaced since the first time are the Zener, the OpAmp, and caps C28 and C2

Thanks! That clears things up. The 3V from the CPU is the problem. The opamp works as a differential amplifier and the level of the input signals determines the output.
With your unit unplugged, measure resistance from pin 21 and 22 to GND. If pin 22 somehow finds a low-ohm path to GND, it would explain the reduced voltage. Normally you should read a high resistance value on your meter.
You should also check for cold solder joints, damaged PCB tracks and anything odd/suspicious in that circuitry around IC2 and the path from pin 22, IC1.

Afterthought: When you measure 3.3V on pin 22, is the supply voltage on IC1, pin 9 still at a solid 5 volts or is it being pulled down??.

The pin 9 on IC1 stays solid at 5 volts whether i operate the < or > button.

As for resistance from pin 21 and 22 to GND with the unit unplugged i measure 46.6KΩ and 44.5KΩ  respectively. Both numbers are not solid, and keep rising (capacitors?). With the unit plugged the measurements are 31.4Ω and 30.4Ω and solid. 

JimT wrote:

With the unit plugged the measurements are 31.4Ω and 30.4Ω and solid. 

😕 Forget these values, they're bogus.
You cannot measure resistance in a live circuit. The multimeter uses its own current and voltage to calculate the resistance; any external voltage results in arbitrary nonsense measurements.

Right now it looks like one of your opamps is spoilt. If you have another chip you can try to replace it -- but before soldering in the new one, measure the output voltages on pin 21 and 22 again. When the dual opamp IC2 is removed there is practically no load on pin 21/22 and both pins should be 5V when the respective button is pressed.
If not then isolate pin 22 completely and measure again. "Isolating it" means removing resistor R53 - and if that doesn't help also C29.
I don't think that the CPU port is spoilt since ports are well protected internally, but the only way to confirm this is to remove any load from that pin.