For the conditional formattong:
You can select the field and go to conditionnal formatting. (right click in windows)
Then set the value to more then x days passed, aand set the amount of days.
For that line choose a fill color of Green.
Then create more lines for the other colors and select a different fill color.
For the IF in the script:
If [PrintedField = "No"]
Display Custom Message Box [Message box text.]
Thank you very much - perfect answer!