Northern Block - missing 1st diary page

[ScuseMe]

Now I know this might be a play issue, but the game does not present me with the 1/3 page of Daniel's diary in the Northern Block.

After completing this level and moving on to the Cistern, I realized that I was missing the 1st page of Daniel's diary. I decided to load a previous save game and get it. But after an hour of searching I couldn't find it. I decided to download a walkthrough and follow it, but I reached the same result - one of the diary pages is missing.

I'm running a Mac through Steam. I thought the developers should know.