Excel - coloring a cell if a given condition is met - wa formatting

Hello, I have such a problem with excel 2007.
I have a table:
-------------------------------------------------- ---------------------------
| A | B | C | D | E | F | G | H |
-------------------------------------------------- ---------------------------
1 | Invoice no. | Amount | Issued date FV | Date of issue FV | Due Date | Today | Formula | Corrective FV No. |
-------------------------------------------------- ----------------------------
2 | FV20130520 | 1900 | 16-8-2013 | 2013-08-16 | 80 | 2013-10-03 | OK / WRONG | 2013-11-04 |
-------------------------------------------------- ----------------------------
I don't know if it can be seen properly, but nevertheless I added the file as an attachment.

I do not know how to do, so that if the date is equal to or exceeds by 80 (cell E2) days, today's date from cell I2 (correcting FV No.), then cell A2 (where is the invoice number, e.g. FV20130034) appears a red background (with the FV no.),
and when the date is not equal to or does not exceed these 80 days, the background has changed its color, e.g. to green, also using the FV number.
It is best if the G3 cell should change the value OK - when it does not exceed 80 days, and WRONG - when it exceeds.
Do you know any way with conditional formatting?

In conditional formatting, use something like this string:

if today> = inscribed_date +80 then color it red

Separately, in some column (let's assume that it is cell G4) you enter the normal condition:

if today> = date entered then G4 = "WRONG" otherwise G4 = "OK"

It is enough to substitute it for the function, I deliberately leave you a bit of my own work, if you learn the details once, you will remember it for longer than if you were given a lazy ready Best regards.

As far as I understood correctly, I did it like this about "WRONG" and "OK":
on dates:

red_background | 2012-07-07 | 80 | 2013-10-03 | WRONG | 2012-09-25
red_background | 2013-10-03 | 80 | 2013-10-03 | WRONG | 2013-12-22
red_background | 2013-11-05 | 80 | 2013-10-03 | OK | 2014-01-24
in cell G4 I entered the function:
= IF (F4> = D4, "WRONG", "OK")
I think it's good for even and greater than 80 days.

However, when it comes to coloring, I don't know if I typed the formula correctly
in conditional formatting-> New formula-> Use formula to specify cells to format -> = $ F4> = 80.
There is a red background, but I have one more question:
How do I know if an invoice is paid or not?

Do you have the "Paid" field at all? Enter such a field, it can be of a date or logical type, if you do not need to keep information about the date of receipt of payment for the invoice and you can immediately filter the paid / unpaid invoice. You can also enter two fields: the date of payment and the logical "paid" - automatically assuming the value "true" if a date is entered in the payment date field (if this field is not empty). In fact, you can insert more of these logical fields, eg "overdue", "over 14 days past", etc. - this is as needed. Then a simple autofilter and you have a quick overview of the situation.

Hello, I will connect to the topic of coloring and conditional formulas.
I am trying to colorize for the condition example AK2 is smaller than AL2 color AK2.
= if (AK2

Hello
Logical is used in formulas in columns AK, AL not "0" as text, instead of 0 as a number

Added after 2 [minutes]:

Then it will be displayed correctly

Hello, thanks for your help, the logic of thinking was ok. At one attempt, the logical sequence turned out to be correct and works almost as it should, there is only a problem with displaying 0 times are highlighted and sometimes not But the formula if (a1