Try to save this selector again, and after that check if its equals to this:
"<wnd app='mmc.exe' cls='MMCMainFrame' title='Visualizador de Eventos' /><wnd cls='MMCChildFrm' title='Visualizador de Eventos (Local)' /><wnd cls='AfxFrameOrView42u' />"
I ask this, because sometimes we hit enter to save. But the change it is not saved.
Here is working properly.
About the -3, it works like this…
We need to find the position of the element that has the size bar, in this case, the size bar is to the left of our element. So, example, it return that the element is in the Offset X 500, then the size bar is a little bit before 500. Then we subtract to reach the size bar.
Yes… this value may up to change. But don’t think as a table, columns and rows think as “eixo X e Y da tela” (by the way, I am Brazilian as well)