Just been playing around to see why things are not working. I can not confirm that DW CC 2018 is working with the both the DataBridge and MySQLi extensions. The issue was the DMX Zone Server Behaviors.
Some time ago it was suggested that these should be used in place of the outdated Adobe Server Behaviors. I have replaced the DMX Zone Server Behaviors with Adobe Deprecated_ServerBehaviorsPanel_Support-1.1.0.zxp (at least I think they were from Adobe) Now everything seems to be working fine so far!
I will report back with any issues as we progress.
Hope this helps some of you.