Having explored further (well, OK, by which I mean "got four of the six dates, cheated with the PDF to get a fifth, brute forced the door open, and was surprised that that was the ending"): still a lot that's interesting. But there's also a lot of what comes down to pixel-hunting: I examined the coaster on the desk early, clicked on it, clicked on the bottom of it, but never realized that there was a hotspot to its right to flip it over. Similarly, looked at the bottle but missed the hotspot for the map; looked at the flowers, moused over most of it, missed the fact that there's something on the bottom of it. (Found all of these things much later.)
I think there's a really good basis for an escape room here, but I also feel like it might need a little tweaking.