I first saw this quilt here, and LOVED it. Some quilts I like and some I love and this one I really, really loved. I had to make one too.
I made a few blocks and got pretty frustrated. I don't know if I have terrible piecing skills or what, but I couldn't get the edges to work. (I should've taken a picture, but I'll try to explain it, and my solution). I basically didn't have enough fabric to trim the block decently. When I trimmed, I was cutting into the point of my square. It bugged me so bad, I put it away for a long time.
But after seeing so many really cool quilts, I pulled it back out and came up with a solution. It does cause extra waste, but I don't care, it was worth it to make it work. The colorful squares are all 2.5in squares, but the white/low volume squares I cut to 2.5x3inches. This gave me enough room to trim without messing with the block. Once I figured that out, I became a granny square quilt block making machine. They are fun.