Forms Personalization at Distribution Line Level Detail (multiple distributions)

I am looking for a sample document that closely describes the process of setting up a forms personalization to Validate the purchase order line distribution and the invoice line distribution.  The personalization needs to validate segment1 of the accounting flexfield against the project/task within the string.  Any examples of forms personalization at the distribution line level for purchasing or payables would be helpful.  Most of the scenarios that I found in the repository don't address the distribution level detail where there are multiple rows that need to be validated.