To make programs robust, you need to have a clear understanding of what the program needs to do. Aka, you need a spec. I couldn't deduce a notion of what the program needs to do from the rambling in the comments, so no pointers of me on how to make it more robust.

I did notice however a curious string: "Chapter \1". It made me wonder what you want to do with the ctrl-A, aka "SOH" character. But then I noticed it's assigned to a variable that isn't further used.