I think the main difficulty with using the Haunted Memories pictures would be that you only get a four-way lenticular change.
Not a problem if you want quite a sudden A-B transformation, but I'd guess that the aging of Dorian Grey would actually require more than 4 steps?
That said, I'm not really sure what else to suggest either
EDIT: hold-up a mo; you've already suggested a projection onto the picture frame....
It would be quite easy - even in something very basic, like MS Powerpoint, to create a multi-stage morph, and would be very controllable too, if run through a laptop projector, surely?
Oh...and you might want to drop a quick introduction onto the forum too (in the introduction Thread, funnily-enough

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