Create a Global Field that you set during OnFirstWindowOpen to get(CurrentDate) - 30
Then use this field in your relationship to show =< (equal or higher) then your Global field
Thanks Johan. I like the idea. But I'm sure there must be another way which don't involve creating a global field.
You can use Portal Filters in your portal
Then you dont use If or Case, your resultat should just be true or false
YourDateField >= ( Get(CurrentDate) -30 )
you might try ...ExpiryDate <= Get(CurrentDate) + 30