In addition to the new features of Smartsheet brought about with the latest update, I'm also now getting #invalid operation error with this formula:
=IF(AND([Start Date]285 - TODAY() = 0, [End Date]285 - TODAY() = 0), "Gray", IF(AND([Start Date]285 - TODAY() <= 45, [Start Date]285 - TODAY() <> 0), "Yellow", IF(AND([Start Date]285 - TODAY() <= 90, [Start Date]285 - TODAY() <> 0), "Green", IF(AND([End Date]285 - TODAY() <= 45, [End Date]285 - TODAY() <> 0), "Yellow", IF(AND([End Date]285 - TODAY() <= 90, [End Date]285 - TODAY() <> 0), "Green", "Gray")))))
Ruh-roh, Raggy. 
There's probably a better formula anyhow, right J.Craig?
Kind Regards,
Preston