Not likely. Their submission guidelines state that anything you submit becomes their intellectual property, in short. I think they figure being in White Dwarf (and being featured in a $30 book) is enough of an ego-booster that they don't have to pay anyone for the entries.
That being said... this is stupid. Really, really stupid. If they had comprehensive painting and modelling guides in it, that might be different, but you know all they'll have for that in there is their basic four step program of "base, layer, wash, drybrush" that doesn't produce results that are even vaguely comparable to what's pictured.
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