I think you did yours right. 10 1/2 inches!!! the 12 inch is evidently a printing error. that was confusing!
the seams you mentioned, when you sew the flying geese section to the basket, don't take too much of a seam allowance. you must sew across the stitches that made the the two colors dip in the center. if you look at the back i'm sure you sewed just on the other side of that and lost your "point".
http://www.ctpubblog.com/2010/05/10/...erfect-points/
lovely block though!!