I don't know where to start, I've think that the plataform behavior don't works in this case...
Do someone knows how to make something like the Flashback/Prince of Persia grid movement?
Try to read this post. Haven't read it myself, but it says solved so maybe there's an answer for you question.
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A couple of ways i can think of (starting points at least).
Platform behaviour has the option to set speed. What you want to do is set different platform speeds for the different parts of the animation (that requires searching for information on how to use animations).
The other way is with time delta. Ive only just started using it but its fantastic. Set a global(or local) variable to count dt when you start to move. That way you could set different movement speeds in a timebased way instead.
There is probably a ton of other ways. Ive only been using the program for a few months myself.
Noga I actually provided a capx some months later in this topic http://www.scirra.com/forum/grid-movement-with-gravity-changing_topic48129.html
But I think how the movement was designed isn't really usefull in a game