Mmm don't mean to sound picky but I'm starting to think the glow is not such a good idea (don't hate me! ). Along the border where its starts, it shows up too bright or something. I looked close at the texture and I have a theory. I think because it's inverted in game, black is light, white is dark, and alpha here is used as brightness as opposed to transparency, the anti-aliased white border fade overlaps the shadow layer so is seen as a very light level of "black". So, in game it shows up very light. It could be a pain to work around. Maybe it's possible to form a selection around every border pixel (the white outline), then generate the shadow around that. It might look strange in the texture but it may look correct in game.
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