Quick question if you are using the GMR AFS1-T why in the image you posted of the screen showing the flow rate set to a pulse rate of 509 pulses per litre? surely it should be 492 or 1200 depending on which nozzle you are using?

Obviously this will have zero impact on the order of the blocks in terms of flow but will mean the flows are actually off a bit (in the case of the larger nozzle only a small bit)