I have run insto a strange issue at a client location:

On an invoice specification, I use the fields C45 - Current Balance and E90 - Invoice total plus current balance.

When a customer has a credit balance these work as expected, for example

Invoice total 100.00
Balance 20.00-
Amount due 80.00

However, when the account balance is positive, say $200.00, I get:

Invoice total 100.00
Balance 0.00
Amout Due 100.00

Invoices is version 6.8B - 040831

Receivables data was originally created in Plus but is now using Adagio Receivables.

I have a copy of the client data and the issue is reproducable here.

Both Invoice and Receivables pass DIC with no errors.