Connection with Mailchimp

Hello All,

We are trying the new Integration between Shopware 5.5.8 and Mailchimp but we are facing the below problems:

1- The integration setup never finish (as you can see in screen shot attached)
2- The step up is saying that customers will be imported as not subscribed (as you can see in screen shot attached) because Mailchimp plugin is not installed but the plugin (last version) is installed on our backend, so why mailchimp can not see that the plugin is installed ?
3- Only customers who made orders are imported to the audience and some are imported as Transnational and some as Subscribed, so why this happens?
4- Customers who register on the shop and still do not make an order are not sychned with audience, so why mailchimp is not able to Sych customers without orders? 

have anyone faced same problems before or can support how to solve them ?