(full disclosure – I'm part of the Avangate team)
Felt nostalgic about your stories, and how Kagi was a true pillar in your growth in the times of shareware / on premise licenses, we’re very sorry to see Kagi close its doors. While those were the days, some of their competitors transitioned to newer models and are thriving with their capabilities as more than payment providers with APIs for SaaS, online services and software on premise with renewals just like their clients. Hopefully everything will work out in the end with your remaining payouts. Not to sound like an opportunist, but I'd like to mention what I believe is a fit alternative to all those that need some help while looking for a replacement.
If you sell software, SaaS or any other digital goods, Avangate is a full service provider, solving the complexity of online commerce, subscription billing, distribution channels and global payments. Avangate is also the merchant of record, eliminating all issues related to local sales taxation, regulations, currency exchange and other account services. But don't take my word for it, hear what the customers have to say http://www.avangate.com/customers/ and also check out reviews on G2Crowd https://www.g2crowd.com/products/avangate/reviews
Good luck!
If you sell software, SaaS or any other digital goods, Avangate is a full service provider, solving the complexity of online commerce, subscription billing, distribution channels and global payments. Avangate is also the merchant of record, eliminating all issues related to local sales taxation, regulations, currency exchange and other account services. But don't take my word for it, hear what the customers have to say http://www.avangate.com/customers/ and also check out reviews on G2Crowd https://www.g2crowd.com/products/avangate/reviews
Good luck!