Well, based on what I've tested, your theory is most likely correct. The main core is out of range and subsequently self destructs. For one of your first bosses it looks very good and complex. Salute to you and hope to see more! And also, welcome to the community!
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RX-12 - Bydo Coefficient Test Unit
"No, don't try and pull any fast ones. There's nothing illegal on the Internet."
"Hello extremely! I hope you like to *play*. Some *campers* are not so good for *games*. Is it time for *playing* yet?"
Asker: How do I remove the border on a GroupBox in .NET?
Answer: Use a panel instead?
Asker: Gee, thanks @$$.