I hope it is OK to reply to this topic. I did not want to start a duplicate thread.
I am having this same issue and tracked it to SMP being the culprit. I am using XP 11.41, SMP 4.6.2, and IXEG 737 1.33. It's odd. I am monitoring my vram and system memory (through the SMP Config screen as well as system monitor) and I can watch the system memory clock off until X-Plane crashes. It only happens with the IXEG 737 and only when the engines are running. Not sure if that helps any.
Some other observations: I have swapped aircraft before the crash and I can see it reclaim some memory, but when I switch back to the 737 it starts to tick down again.
I have attached my log file (all other plugins and custom scenery removed but Gizmo and SMP) and some screenshots that show the system memory clicking down. I left the image names unaltered so you could see the time stamps and how the ram is ticking off.
Great plane ... great products ... I hope this helps find the needle in the haystack. If I can be of further help, please don't hesitate to ask.
B733 - 2020-08-29 16.23.57.zip
Log.txt