Create a Keep as is function
1st off, i love the way your program works, and it has helped my sales grow. I wanted to suggest the following. I will just give an example to make it clear. I edit jewelry photos. Sometimes, i will have part of the photo edited, and when i make a red line elsewhere on the photo, it will cause the existing lines on the first part to change (for example cut into the foreground). This is not a bug necessarily, as the color of the foreground may match the exact color in the background that was redlined.
I wanted to suggest that a user can create a "do not change" zone. or a "done" zone in which no more changes will take place.