Maybe the update that you have mentioned above is for Dokan Subscription and not for Dokan i have upgraded Dokan to 2.4.3 and nothing changed… I suppose that there is need a Dokan Subscriptions upgrade as soon as possible.
From the user profile, you can assign non-recurring pack to the seller. You will not be able to assign recurring subscription package to the user. I saw that you have created a free package which was recurring. A free package can be used once in a time by the seller.
I am really sorry to say that I can not see that error message while enable login in checkout option is enable. I am sorry if I have missed anything. Please provide a screenshot of the error.