Looks like GUI output is broken in KarmaFX Synth Modular 1.x and 2.x on Mac/OSX Big Sur 11.2.2.
Synth shows a blank window when instantiated, without any error messages.
The synth plays sound and is otherwise operational, right click menu works, etc.
There are currently no known workarounds.
I have contacted Apple about this issue, and currently looking in to what could be the cause of this.
Very sorry for the inconvenience.
[FIXED] GUI not showing up on Mac/OSX Big Sur 11.2.2
[FIXED] Re: GUI not showing up on Mac/OSX Big Sur 11.2.2
Fixed in build 283:
Bugfix: Mac/OSX synth would show empty UI on OSX 11.2.2 Big Sur in certain DAWs due to colorspace creation fail. Fixed. (Thanks Ingo!)
Bugfix: Mac/OSX synth would show empty UI on OSX 11.2.2 Big Sur in certain DAWs due to colorspace creation fail. Fixed. (Thanks Ingo!)