Thanks for your reply - happy holidays!
My problems running Shotcut started with version 22.10.25 - which came out the same time my Windows 10 machine decided to upgrade itself to Windows 11 Pro. (That happened when I got a cheap TPM daughter board and plugged it into my old motherboard - but that’s another story).
Although version 22.12 was able to process one of the small test input files (that had previously made Shotcut go nuts consuming memory) o.k., it wasn’t successful at importing a longer (90 minute, 1080x1920) video file - apparently going into a memory consumption loop a few minutes after trying to import the file. So even though they found and fixed some memory leaks, it doesn’t solve this problem for me. Still unknown is why and what Windows 11 may be doing to cause this. Note from the discussions above, nothing really wrong with my hardware configuration - every other video editor I run the same inputs through handles them just fine - and everything else I run on the machine works perfectly, as expected.
I’ve tried going back to several older versions of Shotcut too, but with Windows 11 all of them had the same memory consumption issue that version 22.10.25 and now 22.12 had.
So I’ll hope that they can find some more memory leaks in Shotcut in the future and fix them, since something weird is still going on with these simple file imports to send it into a tail spin on my machine.