I'm on mobile so I cant look at the capx, but I'd use instance variables. Give the object(s) 2 variables: snapx and snapy. Set those values when you want them to be set. On Created, On Drag Drop Start, etc. then when it meets your conditions for snapping, stop the object dragging and set the position to those variables.
Hopefully this makes sense. If not, I can make an example when I get home.