Restarting the program resolved the problem with lack of selection hilight. I’m not sure what was up with it, but as I played with the program more, it was clear that it was not hilighting single clicks at all, even though it was actually selecting things.
Making it into a component sounds like the right thing to do. I will try that.
I also found-that triple-clicking would select the whole thing.
Now, a couple more questions:
I wanted to set the Z-height to a specific value. I found the way to do this to be a little confusing. If I hilighted the (un-pulled) object, and hit p and then typed a number, the number I typed seemed to be ignored. If found that if I manually pulled it to some random value, then I pulled it again I could type a number, though this resulted in the object being moved to below the y-axis. I ended up having to enter a negative number. Was I doing something wrong and/or was there an easier way to set the height to a specific amount?
My goal with this is to make a 3D printed enclosure, from 2D drawings that I used to laser cut and then glue together. So I have a total of six sides, five of which I would glue together, and the sixth that would be a cover. So what I want to do in Sketchup is to take the five pieces that would have been glued together and place them adjacent to each other and “union”: them into one a case that I can print.
2a) Are there tools that I can use to automatically align the pieces together?
2b) Do I need to “union” them in some way so that when I go to 3D print it knows the these pieces I placed together are one object?
I realize this will be a lot clearer if I had some models I could show. I’m working on getting them all imported now.