>Does somebody know if there is somekind of API that would allow to control max button of a form?
>
>I would like to make it look like the form is maximized even if it really isn't.

I don't know if the icons are accessible through the API. Even if they are, I would urge you to not change this. It's usually hard on users when the UI lies to them. You don't say what the situation is. Is the form resizable? Does it have to be? Have you tried setting the form to a dialog, set the max height and width to be the same as the height and width, and start the form maximized? Of course the user won't be able to move the form, though.