can someone tell me how to apply a credit memo in a CSV payment import? i can get it to work when im ONLY paying invoices, and i can get payment discounts to work, but when i try to apply a credit memo in the CSV import, nothing works. it can be done in UI so there has to be a way via CSV.. right?

It can, but I don't think it can be done as part of a payment. Application around CMs is kind of screwy. I think in the past I've had to do a CSV import first to apply the CMs to invoices and then do the payments. It's a pain obviously, but it works.