I have a external hard drive partitioned to 4 volumes. Each volume has back up files. I want to add another partition. I've tried to partition one of the volumes to create a 8 GB partition for a bootable Lion DMG and I'm not sure if I'm doing it correctly. When I choose the volume and click on the + sign, it splits it into two but when I try to make the new partition 8GB, it gives me a different reading and presents it as if there is data in it. What's up with that?