ZBrushCentral

mojave sculpting lag

I can’t work anymore after the upgrade because the cursor moves very slowly under the mouse. While sculpting is even more slow! Done already a clean install of MOJAVE and i see the same terrible lag, then i’ve reverted to osx Sierra and everything works as expected.
info: zBrush 2018.1 (latest) on MAC MINI late 2014 - SINGLE HP VGA display connected via Thunderbolt 2 port.
note: i have upgraded to mojave on my macbook pro 2017 and I did’t have any issue.

edit:
https://support.pixologic.com/PixologicV4/Knowledgebase/Article/View/255/69/macos--bad-lag-or-cursor-skipping

this is the known situation about this bug but i have never used a secondary display.
Anyone?