Two small suggestion before the start of the contest puzzles:
* Make the small dots a little bit bigger or make them appear on a layer above the line segments, so that it's easier to see them, if there is already an end of a line segment in that cell.
* Change the text "Rating" on the page where you choose the stars to "Difficulty rating" if that's the intended meaning. (In that case I'm also not sure if this information, that is based on other contestants solves, should be available before you finish the puzzle.) If that is not a difficulty rating, then it is also not clear what exactly do you want, since a lot of popular sites (like Grandmaster puzzles and the Logic Master Germany portal) uses a star ranking for difficulty and there is already emojis to describe the puzzle.