V5.0.2, but also applies to 5.0.0 and 5.0.1.
Windows 10 Home, up to date, 64-bit.
If I plate up a number of models (STL) and then copy and paste instances, the paste gradually gets slower until S3D crashes without warning.
It disappears from the screen completely, and from the looks of the memory usage, it didn't free up it's allocated memory.
On re-starting, the plate is empty. On a couple of occasions it has cleared the "Recent Files" list also.
I've found no easy repeatable sequence to reproduce it.
