I've got a campaign with a custom deck of tiles that you lay out during play. When the tiles are pulled from the deck directly or dealt to the player's hand they're one size, but when I pull those dealt tiles from my hand to the table they suddenly pop to 50% larger (I'm guessing the tile snaps 10x10 feet.) When they do that, they no longer fit on the grid on the board until manually rescaled.
I can scale the board to match one card size or the other, but contantly have to rescale tiles is a pain. I would imagine that the proper behavior is that no matter if you pull from the deck or your hand that the cards should stay the same size.
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TAZ