Resolution problem

Hi everyone, i just registered on the forums, because i have a problem with the SMB editor (which i just installed).

I have a resolution of 1920x1200 on my monitor, but when i start the editor, the resolution is all over the place (i took a screenshot):

http://img560.imageshack.us/img560/7453/2011050900001.jpg

And the problem is, the crosshair (which the steam's snapshot didn't capture, so i drew it back in with photoshop) is offset, from the point that actually interact with the hud.
As you can see in the screen, the crosshair is under the tile, but "object" is highlighted, even though it's not the crosshair that's going over it, but the tile itself.
This is problematic when i try to set, for example, the size of a new stage, i have to blind click around in the window, to be able to hit the text box for the stage's size.

Another problem (maybe relative) is that.. i actually don't know how to exit the editor!
Everytime i just alt+tab and close the program from the windows bar, resulting in an error.
How can i quit from it? is there a shortcut or a button i haven't saw?

Thanks for your time/help. :)