Don’t use a tag event script. Don’t try to use .getWindow(). Just add a custom property to your image component. Call it “newX”, perhaps. Then, in that component, create a property change event that looks like this:
if event.propertyName=='newX':
system.gui.transform(event.source, event.newValue)
On the newX property, use a tag binding to Prueba/Prueba_1/Variables/MW262.