When the preferences window is open and it is not on the same screen like resolume, then any right click menues jump far away to the right.
First screenshot: Resolume is on the external screen, the preference window is on the screen of my laptop. the right click menue is located far away at the right side of the screen.
Second screenshot: Resolume and the preference window are both on the external screen of my laptop, no problem.
Sorry for the late answer - I don't get notifications, although the thread is subscribed...
The scaling of the laptop screen is "125% (recommended)". The resolution is 1920x1080 (recommended).
The scaling of the external screen is "100% (recommended)". The resolution is 1920x1080 (recommended).