Can you explain this?

I really don’t think anyone in this thread needs a quick fix, understanding is the ultimate goal.

Thanks Vahe, indeed as Box is saying we are looking for the questions not for the fix.
Since I still have the file at almost the same stage I was able to Undo and Redo the steps.

Do you think this could have caused it ? Instead of drawing the line from the tangent I cut the circle a bit. I remember I deleted it lately(not visible in the videos).

Interestingly, the circle does not consist of Edge arc curves, not even Edge curves. They are basic edges with no normal, radius or center. They are not in order either. How was the circle created, was it with a plugin?

I can force them in the green direction with the appropriate arrow key, no problem.
This fixes the problem.
Moving them back in plane again doesn’t “restore” the weird geometry though. It seems to stay fixed.[quote=“Box, post:21, topic:22523, full:true”]
I really don’t think anyone in this thread needs a quick fix, understanding is the ultimate goal.
[/quote] True.
I think the weirdness may originate from creating a loop inside an existing loop where the inner loop has only one common vertex with the outer loop. The circle inside may have had only the most right vertex on a rectangle. And only then the slanted edge was added. @ely862me should know the exact order of creating the geometry. That is important to know.

You can try the rectangle plus circle. ----> weird.

I can move the rectangles in all the ways without any trouble.

The exact order of creating is shown in my before comment. It started with the big rectangle, then the circle, then the two lines started from the circle.

Always avoid creating inner loops with only one vertex on the outer loop. This always seems to confuse SketchUp with more or less unexpected results later on. I don’t have an explanation but this is what I’ve seen many times before. You’ll need to create it with a work around, for instance: circle first, then rectangle.

I experienced the same result of all geometry being selected on triple click.

My experiment:
I deleted a segment of the circle and then redrew the line creating a face on the inside of the circle. I deleted the face triple clicked the rectangles and they were then isolated.

WOW.skp (16,1 KB)

Apart from the fact that I deleted 6,8 KB trash and welding the circle I got no problem.

Ok, no explanation, but I prefer solutions.