it's not at all clear what you did to get the arrangement the way it is. It looks like you manually arranged everything, selected one object, then auto-arrange and got an error. I agree it should not have given that error, but your manual arrangement looks daft Laddie.
What does it look like if you pull all the parts into a fresh instance, don't touch them, let them all be comingled until all are pulled in. Then, with all objects selected in the left pane, select auto-arrange. That's assuming they are oriented in space correctly. If not, orient so each object has the desired 'up' in fact up first. Ctl-L, point at the bottom of the thing, and click it.
Post that picture and your new expression next to it