I have some time today and i did a little test for the backdrop object and the active backdrop object and active object using drag and drop movement.
1.- The behavior during runtime in Windows is different to the behavior in Android.
2.- The second frame is the movement expected as design, to say in some way, but in android is not working.
backdrop object does not respond to transparency value in android and in windows if you set a value different than zero in Blend Coefficient it becomes invisible.
(settings: transparent, none, 15, white, antialiasing)
active object, same problem as mentioned.
Active backdrop object, so far no error respond to set image list, set x and set y as expected.
Windows, you may move with a click of mouse drag the active object and when released move the active backdrop object and set the image list according to alterable value A.
Android, you move the active object using drag and drop movement but "Only one action when event loops" does not allow to set the new X,Y and increment the alterable value A.
Windows, You drag the active object and have the active backdrop is always following the active object and when stopped its takes the alterable value A acocordingly and set the image list.
Android, You drag the objects ans in windows, but it never detect its stopped because the "only one actions when events loops".
Windows and Android it behave indentically the image list is setting 1 and 2 in each event loop and the active backdrop object follows the active object using the drag and drop movement.
In attach the example used
Hope its helps.