Hello, I think it will be really nice if we could listen to changes on the grid. Right now the only way to do that is to create a new brush that will intercept the actions and send a message for you. That is limited however, as the methods signature does not include the brush current tile, you can get it, if you play around with the brushcell, but that is to cumbersome. I suggest a simple set of delegates that will provide the registrar the position(s) and tile(s) changed OnDraw OnFill OnErase and so on for the rest of the actions. maybe even a more general of an OnChange if you do not care for the specifics.