I was so close on this one. I figured out how to go backwards from C1 to S1, but I never understood how the rules are encoded, so I was quite just brute forcing by mind. The big problem was that I neither understood how the word position is translated. For example, "wE~T" which I found as "seat" is in position "1" ("wE~T
1"), but it's the third word in the phrase.
Hey, it was me! I've PM'd OP with some proof. Thanks for the fun and good luck everyone! I won't spoil anything!
We were solving it at the same time! You didn't need to pay $300 for a mining fee, though.

I don't know how he or she made it yet, but I know he or she is smart enough, and I hope you'll all continue to participate in my next challenge, complex rules, double rewards.

Challenged accepted my friend.