The single dots (like in the center of the O, but without the outer circle), when present, are spaces.

S and R are sometimes substituted for one another (I suspect they waffled on whether to be that on the nose with S). I haven't noticed any other substitutions, but I could have missed some, I am not super far into the game. I'll update if I notice any others. Otherwise, not expecting to update this. It's just meant to save others a bit of time if they want to know what the messages mean and don't feel like doing a bunch of screen caps so they can catch letters before they leave the screen.

Note: Some of the text is on the screen for a super short period of time, such as in the intro movie or at least one statue break that I have noticed. It is easy to miss those, so I suggest being ready to grab a quick screenshot when you trigger a cutscene, even a short one, in case you see text appear that doesn't look like it's going to stick around. The text at the start of each puzzle will reappear whenever you go back into the room, so that's not as urgent.