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Just leaving this here because a number of initial reviews mention how frustrating it can be to move around all three of the characters - since they all move slightly different, have different double jumps and so on

If you're interested in the game and the movement has you turned off, don't worry: The devs changed the way group movement works in a recent patch. It's now much easier to control all three characters at once.
Thanks for the info, the reviews about this had me initially concerned but now I'm more keen to try it out.