I have a problem with snap to grid because I have two types of piece. One is a single square (square rectangular grid) and some are 4 times the size and cover 4 squares…
But the fig snaps to centre on one square and overlaps all 8 around it.
Check it out, second post down…
http://www.vassalengine.org/forums/viewtopic.php?t=1004&start=15
Anyway I will be trying to find a work around or fix; but any help will be much appreciated 
In your grid settings allow snapping to corners and edge locations. This will allow the piece to cover 4 tiles properly.
The drawback of these snaps are they are universal to all pieces and cannot be selectively specified to one piece or another - feature hint 
— On Tue, 9/16/08, danjaman messages@forums.vassalengine.org wrote:
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Another workaround is to make part of the piece’s image transparent. Make the image large enough to fit 3x3 squares, but only color in the upper/right 2x2. Combine this with a Non-Rectangular Shape trait so that clicking on the transparent portion doesn’t select the piece.
rk
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Thank you very much for your prompt answers, rk. I had thought of the transparency tweak; but was worried about turning issues…
Back to work