Clockwork and Cryptography: Angelmaker Code Hints, Part 3

My dear fellow cryptographer,

May I congratulate you on your perseverance? You've been plugging away at this code for quite some time now, it appears. Well, perhaps you haven't - perhaps you've just googled "Angelmaker code hints," blew right past my admonitions to not read the hints, and started reading hints 0, 1, and 2 straight away - but I'll give you the benefit of the doubt. 

Some suspicions about the nature of this code should be forming in your mind, and you may even be starting to test out a few theories. This is a good thing, and all the more reason that you should IGNORE THIS HINT AND SOLVE IT YOURSELF. You'll be so proud of yourself! This is a code that was meant to be broken, and it was meant to be broken by the likes of YOU. Go solve it, you young Champollion, you, and let me know when you're done. 

Still here? All right, then. I did imply that you were dedicated. Here's the third hint:

You're looking at a monoalphabetic cipher with a twist.

In a monoalphabetic cipher, one ciphertext symbol stands for one plaintext symbol. The very first code you ever broke was probably a monoalphabetic cipher, and most likely a Caesar cipher at that (you know, where you shift the alphabet however many letters to the right, so that A is encoded as E, B as F, C as G, and so forth). This is obviously not a Caesar cipher (there's no alphabet to shift), but the ciphertext symbols have a one-to-one mapping with the plain text. Now, that's a gigantic hint if you haven't made a particular realization yet, so I won't elaborate any more. (If you have made that realization...er, sorry. Getcha next time.) Go look at the picture I posted in Hint 1, then come back and read this hint again. Hopefully, you'll have one of those lovely "aha" moments that make codebreaking so satisfying. 

Oh, what's the twist? Not telling (yet). Sorry.

Happy codebreaking!

(If you need more help, here's Hint 4.)