• Open VAB with no vessel in it.
• Add IMC-22K as a root part.
• Add another IMC-22K on top of it (the manufacturer doesn't recommend doing it, btw).
• Remove and dispose the part from step #3
• Repeat steps #3-#4 multiple times (3 to 12).
• Crashed!

As of now the bug is tested and identified! The reason is understood, and the fix is on its way.