UD-3900 & Lenovo display on OSX - issues

I’m using the UD-3900 docking on an iMac. It is up and running, but there’s some issues with the support of the external display. Again, running the latest OSX version - OSX High Sierra 10.13.2.

The external display is Lenovo LEN LT225pwA 22 inch - it often does not display as expected - usually replaced by black / dark patches in certain sections dependent on the application. The display has no faults as I have used it plugged directly into another machine and it works perfectly fine

Does the UD-3900 have issues supporting some displays??