Answer
As far as i understand, editing existing grids will confuse everything
1. Adding more fund = how do profit calculated? from initial investment, or after addition? If so, then the graph would looks bad since after addition will having a cliff. If its not, then it will be more confusing for calculating the profit (from where?)
2. Changing grid number and Range = it means will cancel all current orders since the price where the orders will be put all will be changed , imagine using 1000 range 11 grid (100 interval) and then changin it into 900 range 12 grid ( 88 interval). It is the same as closing the bot and creating new one
For adding more fund, you can always run more bot (Up to 30 per pair, which is a LOT. per pair). We can always work around things we want with the tools, just be a little creative