Multistage Stochastic Programming using EMP extension

[ujrai1]

Hi,
I am having some issues with stochastic programming problem using EMP extension.
Block diagram of my model looks like this;

The max Generation capacity of Generator is 1500 KW, the whole year's site demand probability distribution is given. At each demand level, there is a probability of having (Yes) or not having (NO) a dispatch call for the generator to export extra power.
For site demand, there are 5 scenarios and for each demand level, there are two scenarios each, so in total 10 scenarios.
My question are;

1- How can we correlate these two (site Demand & probability of having a dispatch call or not having a dispatch call) in multistage stochastic programming using EMP extension?
2- Should it be a 3 stage stochastic problem or a 2 stage with 2 random variables?

Thanks