problem using conditional formatting to flag cells by color and count them

Any help would be greatly appreciated! I am using Excel 2003 and am not sure how to use the conditional formatting. I have attached an example of the workbook I have, I'm sorry I could not attach the actual one b/c it contains patient information, however this one is set up just as I have for now.
What I don't know how to do is color the In Date box a certain color if there is no completion date entered w/in a certain number of days.
So if there is no COM DATE entered 10 days after the IN DATE I would like the IN DATE cell to turn yellow.
If no COM DATE entered w/in 20 days after the IN DATE - orange
no COM DATE w/in 30 days - red.

After the IN DATE cells have been colored I am wanting to count the number of cells w/that color.

I hope I have explained this appropriately and that the attachment helps.
Thanks in advance for any help!