Secure Remote Drobo Access without MyDrobo service

Hello, I want to access the Drobo Access service outside of my network without using MyDrobo as it’s slow… I get around 1.5Mbps downloading files from the box using MyDrobo VS 30Mbps when downloading direct from the box using just Drobo Access and port forwarding.

However using the latter method I can only connect to the box using my WAN IP, which is fine, but it doesn’t support HTTPS (encryption). When I try connecting to the box using HTTPS I get an error message:

SSL received a record that exceeded the maximum permissible length.

How can I enable HTTPS support for remote connection to Drobo Access? Is there a different port number?

Thank you.