Azure HD Insight 3.5 and Radoop: cannot get it to work

Hi, I want to connect with RM Free Edition 9.3 using Radoop Basic to Azure HD Insight 3.5+ and using Spark 2.2. I have everything setup as suggested in the manuals and forums. I imported the cluster info from Azure in RM. In Azure all services, including Hive, Spark etc. are working. Using a test with PowerBI via the connection to Azure works fine, Hive and Spark can be used in PowerBI. Using RM and Radoop I cannot get it to work: it keeps failing on the Hive connection when testing the connection in RM using Radoop (Hive server 2 connection: ). I checked all Adresses in the Radoop Connections Screen (Resource, NameNode, Hive Server), all are correct.