I decided to do a quick fitting of the corner blocks and noticed that I have about an 1/8" to 3/16" gap between the top and bottom piece. In looking at other pictures of them it appears that they are always touching each other. Do I tighten them down that much? I will try to take some pictures of it tomorrow.
You may be referring to the renders. but I can say, mine have about an 1/8th inch gap in mine too. and what Ryan said initially was, do not tighten them down too much, it isn’t necessary to do so and it will put unnecessary stress on the plastic.
No they do not touch and should not.
When you put the screws in they need very little tension and you are trying to keep that gap the same all the way around. Just tight enough for you to feel drag if you rotate the rails by hand, they do not need to be locked in place.