HELP~~~~~~~Conditionally Formatting *Warnings* or *Reminders*

For example if the first row were headers: Name, Quiz Grade, Exam Grade, Average Grade, Bonus, Final Grade

Lets say that you entered a name in the 'Name' field (A2) on 10/14/2014(referencing system PC date & time.)

if the 'Quiz Grade' field is not updated by 10/16/2014 (2 days past) (referencing system PC date & time) column B is highlighted yellow
and if the field is not updated by 10/19/2014 (5 days past) (referencing system PC date & time) column B is highlighted red.

So basically its like warnings for yourself to update certain fields on your spreadsheet and reminding you to fill them in after filling in the previous cell.

So basically you fill in A2, then gives you 2 day past due warning in B2 in yellow and 5 day past due warning in B2 and so on.

Lastly I want to no fill if that cell is filled in. I'd assume that would be no fill if that cell > 0