That puzzle was incredibly obnoxious. First of all, you put some of the letters in optional dialogues. For example, in the first controllable scene I was asked to determine who Sally is in this scenario. I immediately clicked on the dresser, which let her use the mirrors to get a look at herself. But by being smart about it, I denied myself the opportunity to check the bed which gives the Y. No matter how much I looked back and forth through the history section, I couldn't hope to solve the puzzle because my history was missing a bunch of letters. And the plot seems to imply that Sally should try to solve everything quickly so that she doesn't rack up as much sleep debt. Second, proper nouns. Early on someone mentions an "Anomaly". This isn't a word that people usually capitalize, and elsewhere people talk about "anomalies" (no capital), but as far as I can tell it is not supposed to be part of the puzzle. A bit later, someone mentions a "Warp". This word seems just as likely as Anomaly to be something that this particular organization would use as a proper noun unlike normal people, but as far as I can tell I am supposed to be including this W in the sentence. Third, sometimes after two or three consecutive periods you capitalize the next word, and other times you don't. I didn't see a spot where I concluded that I was supposed to count it, but I can't be sure because it combines with all the other uncertainty.
By the way, Sally is told that she will be warping to the XVIIth century, but on arriving she declares that she knows she is in the XVIth century.