Long story, but basically I got an "invalid sibling error" on my intel IMac and was told the best fix was to zero the HD and reinstall. I did this and got Leopard running. Now it hangs while I try to update to 5.10.8. I downloaded the combo update from Apple after it failing through system update. I'm not sure what the issue could be. I've verified the disk, checked it's smart status is ok and run the hardware test from the install disk. Any ideas?