A tweak on these machines which I particularly like is to route the light plastic line, which goes from the top of the OPV across the machine to the drain fitting, to the top of the reservoir: it keeps the shallow drain pan from overfilling, doesn't waste water, and makes the flowmeter seen only on touchpad machines truly functional,
Just unscrew it from the tee, remove the tee, and reconnect the line from the three way valve directly to the drain fitting.