Exclude credit memos from autocash

Hi everyone,

I have investigated this from every angle I can think of, so now I am reaching out to My Community.  Is there a way to exclude credit memos in the algorithms Autocash or Automatch uses to autoapply a receipt to a customer's transactions?  Perhaps via the setup of the Credit Memo transaction, the Lockbox, the Autocash or Automatch rules, etc?  For example, a customer has one invoice for $200, a second invoice for $100, and a credit memo for $50 all on Oracle.  Then they send in a payment via lockbox for $300, The Clear the Account rule is turned