Yes we are using the 3.0.X version of Orient DB. Currently 3.0.32. You can certainly install convergence on your own server and you can point to an existing OrientDB if you like. The “omnibus” container of Convergence contains an embedded OrientDB for convenience, but we have individual containers that can be deployed that can use an external Orient DB.
For Distributed mode, I assume you also mean deploying a Distributed OrientDB cluster. We have tested that out recently. It seems to work but there are some things you need to make sure you have set correctly, like the write quorum, etc. We’d be happy to discuss.