I will take a look at the things you provided and hopefully be able to get this working. Is it OK if I wait until then to mark some answer as correct?
My answers do not solve your issue and I cannot definitely state whether it’s even possible, so marking them as correct would be an exaggeration in any case.
Nice of you to give this some thought, but you need not use the the correct marking.
How do you know what the strings you have to pass to the ActionReference have to be?
Well, I’m not really comfortable with AM code myself, so I don’t know either for this case or even if it’s possible.
And like I said the Window’s dimensions do not seem to be accessible through Scripting, so the whole issue may be moot.