How long should I bake it in a 9" pan instead of an 8"? THANKS FOR YOUR HELP!

The cornbread will be quite a bit thinner in the 9" pan than in the 8" pan called for, so you'll want to dial the time back considerably - especially given the comments that the cornbread is crumbly. (That suggests to me that the people who have had that problem may have baked it too long.)

I would start checking at 12 or 13 minutes, being super careful not to let it over bake. Better to start checking a bit of ahead of time than to let it go too long. ;o)