Setting recurrent dates in a cell

MoMo71880 

How is this for a simpler solution. Just use conditional formatting to turn the Next Order date red if more than seven days have passed without an update to cell A?

Here's the conditional formatting formula

I've attached a spreadsheet that uses this example.

It ends up looking like this when you haven't updated the "Last Order" date.  If you have, then the cell appears as a normal (no highlight) date.