Window always on left screen border (all resolutions)

[monogon]

Hello!
Sorry if this is a basic question. In my game I want to have a window that slides in (with TweenPosition) and always sits at the left border at all resolutions (android).
Currently the window is too far right on some specific android resolutions. I made an album to show what I mean
http://imgur.com/a/mhSo9

I tried different anchor settings which resulted in the window being cut off at some resolutions which would be the worst case (not being able to read the text). Can you help me please with the anchoring settings so that the window always is left at all resolutions?
( I am using the fixed size on mobiles setting)

Edit: Ah, I think I understood something completely wrong ... Anchors have no effect when using Tween Position, right? So I would have to calculate the Tweening Values for the specific device the app is running on ...
But how would I do this? Any hints? I want the window to slide in from off screen to the very left of the screen.

Thanks!

[monogon]

I fixed this by setting up an anchored invisible widget and tweening the window to this position. This should work on all devices and was the easiest solution for me.