VWAP ENGINE is simple enough to see whether to buy or sell. The area where professionalism is called for is in Money Management.

Cable MeanBoxTrendLine

It's simple- blue for buy, red for sell.

EURGBP BUY into blue zone

Buy when it comes into blue zone with stop just below yMean.

60ATR is 10pips, so targetting 22pips and then 60pips (80% of Day ATR 76pips).

EuroSterling turning points

This is an example of vwap engine application on forex pair EURGBP. I think it should be called FX Engine.