Multiple EMA AFL

Hello All,

I need some help on an AFL which will plot the following. The below helps in identifying the trend.

Let the Oscillator name be EMA-Difference-Oscillator

a) EMA ( 5 ) - EMA ( 15) will be plotted i.e. Difference of value of 15 EMA & 5 EMA but it should be 5EMA - 10EMA. The difference will be plotted as percentage so that it looks like an oscillator ranging from positive to negative values.
b) If the current day value of this oscillator is higher than 10 days ago , need a ribbon at the bottom which will turn green. Ribbon to turn Red if the current day value is less than 10day ago value.

Any help for this AFL will be highly appreciated.