phartron
what may be happening is that the top left corner of the screen is no longer 0,0
So, you can try Pin, but I usually have an event:
On Browser Resize -> Wait 0.2
-> Sprite - set position to ViewportLeft(0), ViewportTop(0)
since the origin of your sprite is the middle instead of top left corner, you would have to do:
Sprite - set position to ViewportLeft(0)+sprite.width/2, ViewportTop(0)+sprite.height/2