the issue at hand is explained in 2 previous posts/threads.
basically QS was crashing after a time. It seemed to be most often when editing custom Triggers. I had thought it was an audio plug-in for Pro Tools, but now I think not.
The plist I used I had used just a few days before when taking my unsupported 2013 MBA to Sequoia via OCLP.
The MBA and QS and Sequoia are just dandy.
I decided that even though I had success with that plist and the MBA, perhaps it has become corrupt.
So today as I built back Sequoia onto my 2018 mini for the 4th time (even after an Apple DFU Restore), I decided to add custom triggers from scratch and not use the old plist.
So far so good.
2 issues. I can't get QS Triggers to accept Cntl/Cmd/D or HyperKey/Q. (HyperKey is provided by Karabiner. I was thinking there was some OS conflict with either of those shortcuts, but can't find them.
If anyone has a suggestion ...