I'll try: As I said, at some point during the second stage, the game gets stuck. I can select and "place" buildings, but nothing happens (they become green aka "I fit here" and show me how much I would earn). I am still holding the building, no currency gets deducted from my funds, and nothing gets build. As if I hadn't placed it. Selecting a different building and/or spot makes no difference.
SCREENSHOT: As you can see, I tried to place an upheaver on a stone tile. It's green and I have enough money, so it ought to work. I click to place it, and the green radius that is normally there to tell me its range disappears, but no upheaver gets placed nor do I spend currency. This happens no matter what bioms I have completed until then, but so far I usually always have startet at least all but the forest one (in this case Forest was done first, but I have some for all bioms). It happened in all games so far, and my progress was ranging from below 20% on Stage II to almost 40%.
In addition, when pausing the game with Esc, I cannot use the the "return to main menu" or "exit" buttons. they click, meaning their border gets darker and they make a sound, but nothing happens. Up until this point all features work just fine, maps unlock, etc. .
However, it is possible to "fix" this error temporary: By closing and restarting the game, the last move is undone, meaning I am in a "pre-getting-stuck"-state. When I do something else this time, meaning placing a different building on a different spot, it works. But the error occurs sooner or later (more sooner, as in one or two placements later). I can repeat this process a few times, but at some point the games always gets stuck.
I am playing on Windows 7, 64-bit. Using the 32-bit file makes no difference, I tried it. It works fine on my Linux-Laptop (Manjaro), but I couldn't try it on a different Windows-machine yet. The game is NOT installed on C, if that is of any importance. Starting the program as admin has no impact.
PS.: I can make more screenshots if you wish, but I don't think they'll do you too much good, as it's not exactly a "visual" type of error.
PPS.: I played it a bit on Linux, and I love it! Stage III is amazing!