Nothing's stopping you from not reading something that looks too long for your attention span...
And I'll keep saying that no game review I ever wrote would fit into GOG's limit. 2701 characters for the shortest, for a little VN, and that's an odd one out, way smaller than the rest.

I don't know how to separate your two sentences, but what you describe in the first, happens to me when I read reviews in Steam (without being subscribed there). I search for the small and more terse reviews. Most others are too long.

However (about your second sentence), that happens to me when I try to post a game's plot in Wikipedia. I usually write in much detail (so that the readers can follow the story without missing something) and most often my reviews are being rejected/reverted!! (as if there isn't enough digital space!!)

For me it's another thing to write an opinion and a totally different to write a plot. The plot isn't an opinion, it's something standard and have to be written in full, so that the reader won't miss anything in the flow of the story.

First time I see this.

I just posted a review for Shadow Warrior 2013 but it doesn't show up. Also, it doesn't seem to remember the score I want to give it. I pressed the wrong amount of stars and now it doesn't want to save the new score.

Just to try the basics first, tried Ctrl+F5, to force a refresh of data too?

Sorting by most recent I see your review on top, four stars. I think it used to be possible to change your stars after leaving a review but it doesn't look like that is possible now. If you really want it changed you can ask support to change the number of stars, I'm guessing they would be able to do that.

It did show up after a few hours, but it still put the wrong rating there.

I'll ask support to change it, cheers.

It's a shame that after so many years of asking you still can't edit your review, or have some kind of overwiew of the reviews you left.