Crashing models

I’ve been having problems with files crashing for a while now. I’m on an iMac running Mojave, and SketchUp often doesn’t quit. I can finish work, save my model(s), close them, then when I quit the program nothing happens. This is only solved by force quitting the application. Sometimes (but less frequently), SketchUp will just crash out and create a bugsplat report.
… is this to do with the origins of objects I’ve brought in from the Warehouse and/ or other online sites?

A recent file is here. It usually works, but crashed twice today…

It could have something to do with one or more components you’ve imported from the 3D Warehouse. It might also have to do with your modeling. You are using layers incorrectly putting geometry on layers other than Layer 0 and making other layers active. I cleaned up the geometry putting it all back on Layer 0 where it belongs.
Screenshot%20-%207_1_2019%20%2C%201_09_23%20PM

I also purged unused stuff from the model.
Screenshot%20-%207_1_2019%20%2C%201_07_24%20PM

After that it saved just fine for me.

The layer0 thing will be a hangover from old days using Microstation. There was no constraint so you put stuff on any level then turned off and on as needed.
How do I check re origins? Do I have to open each component/ group in turn?

If you want to see the component origins and axes you can make them visible in Window>Model Info>Components. You’ll see the little red, green, and blue axes for the component.

The toilet looks like it could stand some cleanup. Notice the size of the bounding box. It probably doesn’t need the internal geometry for the bowl.
Screenshot%20-%207_1_2019%20%2C%201_37_41%20PM

The sink could stand to be simplified a great deal. Currently over 46,000 entities (edges and faces) in it.

You might consider importing Warehouse components into a separate file and then take a few moments to examine and clean them up before sticking them into your main model.