Current reading, how does it work?
R7 is the current sense resistor and it has a value of \$0.5 \Omega\$.  By measuring the voltage across R7, you can use Ohm's law to determine the current through the resistor.  The reason it has such a low value is so you have as small of a voltage drop as possible.  This allows most of the voltage drop to be across the motor.  R24 and C3 are there to act as a low pass filter to help smooth your current signal out.