As a new user, something that is really confusing is that if you import a prop, save it, apply it to a character in Composer Mode in the proper position, and then go back to the stage, the prop will be the wrong size and in the wrong place. This doesn't make any intuitive sense at all. I had no idea what I was doing wrong.

See Why does prop placement stink so bad?.

When a prop is added to a figure in composer mode, all the transforms should be reset so that when you exit composer mode, the prop will appear as expected on the character the way you positioned, sized, and rotated it in the character composer.