I am trying to puzzle out how to create a "due date/renewal reminder" setup where the user can find out which records are due/unpaid etc., preferably using a button/script setup

I have an auto-created field 'created' and another calulated field 'due date'. The calculation is "Date(Month(Created) + 12; Day(Created); Year(Created))", which I think gives me the first renewal date for one year ahead. But this of course has a logic flaw, i.e. what happens years 2/3/4 etc.

Any suggestions or examples would be appreciated. Hope this is the right forum.

A general comment. Presumably there is some sort of "renewal" entry. At that point you could update the due date by one year. To show the user all the due renewals you could use a scripted find or you could create a relationship which would pick out all the ones that are overdue. This is the advantage of the new FMP7 relationship model you can use matches of the form DueDate <= Today

Presumably there is some sort of "renewal" entry.

Not at the moment. I was expecting to have to do something like a Radio Button or check box field, to indicate a renewal, which would then somehow update the due date field by another 12 months.

But a) I don't yet know how (only still x hours using FM) and I was wondering if there is a better way.

Keeping it simple - updating the renewal date by another year should be enough to indicate that you have had a renewal so a button scripted to do that should do the job. But do make sure that you take account of the possibility of accidental clicking in some way. At the very least a custom dialog asking Are you Sure?