Arduino motor shield orange/white pin usage
...which pins are mapped to the data pins etc.

The shield page provides a schematic

I would like to know some more information about the orange and white pin blocks on the board

These have the reference printed on the board


TWI IN and TWI OUT
They are the same and are both connected to the same I2C pins of Arduino (SCL, SDA). They are intended to help in case you want to connect more than one device.


OUT 5, OUT 6
Connected to Arduino pins 5 and 6 (PWM outputs)


IN 2, IN 3
Connected to Analog in A2 and A3


The power outputs of L298 intended to drive the motor are the blue screw connectors.