Sanctuary – “Crimson Tide” [Campaign 4 – Mission 3]

I complained myself, I figured it out myself, I'm writing the answer for myself – in case someone else encounters the same problem. After the darkening video and the screen blurring, you need to move the hero to the end of the turn, click "next day" (I have autosave enabled – simply saving and then loading didn't help), exit – IMPORTANT! First, go to the main menu of Heroes, and then – exit to Windows. I don't know how to explain it, but if you simply exit the game to Windows without going to the main menu, and then load, it will all be dark again, and if you do it this way, something seems to "click," the save is shown as dark, but the screen loads normally. And by the way, removing the "data movies" folder doesn't help, because this folder doesn't contain them – I have the latest version.