That's certainly one of the more interesting takes on Galv's gun platform mode. Looks like some kind of crouching crab beast thing with a gun. I like it.
I call that epic fail. Not because the mode looks like crap, but because I can't imagine Galvatron turning into that.
On the other hand I can imagine Galvatron transforming into it. I don't see a walking tank (though it is), I see an artillery gun on a raised mount with a gun pointed backwards. Point the gun the other way and voila - a futuristic artillery gun in a deployed state.