Motor driver chip install direction?
From A4988 Stepper Motor Driver Carrier, the rear of the breakout board, is identical to yours:



Note the two square pads for the GND, whereas the others are round. Now looking at the top side:



and note the position of the square GND pins/pads, in relation to the trim pot.

Now look at this hi-res photo of a populated MKS board



Again, looking at the position of the trim pots, one can see that the A4988 breakout boards need to be oriented such that the side with GND pins need to be nearest to the top of the board. That is to say the GND on the corner of the breakout board, needs to be pointing North East, as it were.

Here is a schematic of the MKS 1.4 as well, although it is not much use, from MKS Gen 1.4 circuit and pinouts: