The blotch - try rotating the model ever so slightly. I've heard of shots at certain angles giving weird results - 90, 180 or 270. Try adjusting the shadow map size to a higher number as well. The seam - are you on P5? If so, check the Max texture size. I've had seams show up if the Max texture siza was 1024 when the texture itself was 2048. (Boy, did I go nuts trying to figure that one out!) Hope it helps!