After a few teething issues with the payment functionality that undoubtedly lost me 1-2 other sales, I learned that the flow caused way too much friction.
So after following the most important Indie Hacker mantra of speaking to customers, I refined the checkout to only require an email address instead of SSO full signup. This meant the user did not have to be redirected and thus the total from choosing a number of licenses to entering a card number, it was just 3 clicks.
I am still working out some of the other kinks and UI bugs on the website, but I am so happy with what I have built so far.
As for progress about the MacOS app itself, that is coming in a few days. So if you haven't signed up the SprintDock Mailing List