Question related to agg/spread method.

I have two questions:

1) Have a editable measure "C" with aggregation as average_pop and spread as replicate. This measure is not calculated from any measure and it should hold user entered values at base intersection. There is a request to change the aggregation to recalc, so the measure shows values at aggregate level as A/B and no change in base level. Is this achievable?

2) Have a editable measure "X" with aggregation as average_pop and spread as replicate. There is a request to change the spread type to prop.

For example child cell have values 10,10,20,20 and parent shows 15. If they update, 25 at aggregate level, expectation is 20,20,30,30. Actual result is 4.17,4.17,8.34,8.34. Is this achievable and how?