Connect drive to Dropbox/Google/Microsoft broken?

Hi! After initial very good impression of mailbox.org I am now a little worried.

My problem is I wanted to connect drive with an external service. Seeing the many options first was reassuring but I now have not been able to connect to:

- Dropbox (https://userforum-en.mailbox.org/topic/3896-dropbox)

- Google drive (https://userforum-en.mailbox.org/topic/3976-cant-add-google-drive-to-storage-accounts)

- Microsoft (couldn't find a thread, but got similar error as with Dropbox)

I also read reports of e-mails getting blocked by (corporate) receivers (https://userforum-en.mailbox.org/topic/4656-sent-emails-getting-rejected-by-corporate-email-systems) and on my created support ticket I immediately got a response warning me of unusual long response times.

I understand that the new interface launch together with high inflow of new customers are creating a workload which maybe explains everyting, I don't know.

But the Drive option to add external storage accounts from Dropbox / Google / Microsoft all are broken which does not look good. Is this service in beta?