This occurs when the DGN graphics representing GPK items is out of sync with the GPK. Where I have experienced it is when I have (usually on purpose) deleted the graphics representing some of my GPK survey points. In my case, the deletion was on purpose and the GPK just needs to synchronize itself with the current state of visualization. Although the message is a little scary, it is nothing to be concerned with, IN MY EXPERIENCE.
JUST A THEORY: The crash reported in the original post must have been caused because of a great many deletions which needed to be cleaned up and the work of doing eventually used all available memory.
JUST A THEORY: The crash reported in the original post must have been caused because of a great many deletions which needed to be cleaned up and the work of doing eventually used all available memory.