There are currently 3 unlockable CGs in the public build.
One on day 5 (not Erik's), one on day 6 and one on day 8.
To unlock these scenes, you have to have made good decisions and have enough points with the character with whom the event takes place.
Not all points are required to unlock it, but almost. If you select the dream at the beginning of a specific character it will be easier to unlock his scenes because they are 5 extra points.
And I've already said too much :3