Your experience with the file layers reminds me of how my partner routinely wishes a curse on the head of all commercial programmers that they will lose a year's worth of work to see how it feels when consumers end up losing their work because of some stupid update they've done.

Also interesting to hear about summergen. I remember this challenge and it's great that it's still going on. It's surprising how often a fest or exchange will keep a fandom going long after the canon ended. Merlin has several of them as well.