Thanx for taking time to give a very nice and (for a dummie) understandable reply!
Main concept: Its a calculator on top of HA! Great explanation!
Q1: Why do I want the config data? - Cause ther is so much “YAML/ code” floating around with the setup, so it was for me to be able to “see” i was doing the right input, and be able to use the copy-paste programming method 
Q2: OK. So the name in UI sensor_power_photovoltaics is a misleading name. Its more of a variable, that gets its input from the HA sensor that i provide?
Do i understand it correctly then that what i specify in the EMHASS UI as the first three “sensors” ( varibles) in EMHASS ( Sensor power photovoltaic, Sensor power photovoltaic forecast, Sensor power loads with no variable loads) are NOT to be “HA sensors” with actual production values (like the PV production sensor in kWh), but are to be populated by a string /Array of information “sensor”.
If using “day ahead optimization” it has to be arrays of data with a certain granularity of my choice, for 24 hours starting at the restful/shell API call.?
Thats what i have to look further into i guess!
Q4: What about the " Sensor to replace NAN values with 0s" and “Sensor to replace NAN values with linear interpolation:”. Are these the output variable/list?
Q5: The “Tariff” part of the UI: Here I can only chose between “constant” and “csv”. How can i define the input “sensor/variable” for the Tariff array? I suppose “load cost” is the same as import price and PW power production price is export price.