How did you generate the column that subtracted the dates? Did you use "DateDiff"? That should return a "real" value which should work fine instead of an Integer.
Here is an example:
I have two columns Today's date, and Date Created.
Step 1: Calculate Days between the two columns using DateDiff
Formula: DateDiff('day',[Date Created],[Today])
Step 2: Create your new column with your case statement.
Formula:
Case
When [Days Open]<5 Then "Tiempo"
Else "Late"
End
Those are just examples, I know your #s are slightly different but the concept should still work for you.
