That does clear it up a bit more for me thank you Timmy, the thing that seems odd though is when it's first automatically mapped, the UV"s fill the whole UV space, and the checker texture looks good on the model. But then say I want to rotate some of them and re-lay them out so that they don't overlap. Then Packing seems to shrinks the whole square down. I kinda just wanted to scale the whole block of islands so that they filled the entire UV space. As it is the UV block covers less then a quarter of the space. Technically I could scale the block up in Maya, but it seems like it should be filling the space in 3d Coat?