Hi Adrian!
Yes, you an use a microwave. But you have to be very careful. Per the manufacturer, using a microwave means you should be heating the clay in bursts, always checking in between how soft it is in order not to overheat it. Since microwaves are much stronger, this process will take a lot less time than in the oven.
Never put a figurine with armature into the microwave though. That will cause a hell of a lot of problems, seeing as metal of the armature and microwaves don’t go together under any circumstances.
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