I have a 2008 macbook air which is not booting. It was booting to a Bootcamp partition, so I tried booting to a linux live USB and repairing the partition map with Testdisk. But now, it doesn't boot at all. I have no backup of the information on the hard drive, so I would rather not format and reinstall the operating system. From my fairly brief stint using linux a few years ago, I can remember manually editing the startup config to select which partition I wanted to boot from. Is there anything like this I can do when booting from a Lion USB?