I heat up a coffee mugs worth of water in the micro, warmer than I would for my coffee but not by a whole lot. This works great, although none of my stuff has crashed or solidified yet. When I used to do this all the time over a pot, I had a fork that had bent tines so that it held the cap on the vial and I could suspend the vial over a pot of water without me burning my hand.
My test enan "powder" though did finally solidify in its jug, when it arrived it was liquid, but its been cooler lately.