So I've found so far that if two metal points are in close proximity of one another (like in the picture), you can only build 1 metal extractor on either of the two points, but not both. Seems to me like a bug where in the process of rendering a system/planet, the metal points are placed too close too eachother. It's the second time in three games I've encountered this. And although it's not nececarilly a problem, it bugs the hell out of me! So, bug? Or just something I should try to ignore as it's intended?
Sometimes if you rotate the metal extractors while trying to place them, you can get them to both fit, but I agree that this is quite irritating. They should auto-rotate to fit if possible.
Metal extractors are wider than they are long, hence rotating them can make a substantial difference.
I don't understand what you mean by rotate. Isn't there a big thread full of haters on just this topic? Rotating unfortunately doesn't exist. To my great dismay people want "simplicity" instead of complexity and customizability. (Won't let me post link to thread for some reason. Silly forums.) Title is: "Structure-facing" For now - can't rotate them extractors.
Just hold click and drag to rotate a building as you place it. Also, as far as I can tell, T2 and T1 extractors have the same collision volume. If a T1 can fit on a mex, a T2 can fit on it also.
Altho it's not the advanced metal extractor, i believe the normal one has the invisible size of a advanced one.