Hello, 
In Composer Mode, the Sprite Editor is previewing the character sprites and sprites position so it will change the default sprites when back to Stage Mode.
If you would like to switch sprites of the hand must be used sprite editor in the Stage Mode.

But I should be able to use the character with a new sprite, right? Currently in compositor the sprite editor comes up, I replace the sprite & close the editor & the sprite reverts to the default, I can't get it back to stage with the change. When I change a sprite (say a hand sprite) on the stage, it changes, but when I add a motion, it reverts back to the default. 

My PC
====
OS: Windows 10 Pro x64
CPU: 4.00 gigahertz Intel Core i7-6700K
MB: Gigabyte Z170N-Gaming 5
RAM: 16GB DDR4 2133
HD: 2-2TB Western DigitalCaviar Black
VB: EVGA GTX 980
DirectX: 12


"Sure you can trust the government, ask any Indian."

Hi, your issue is the face accessory and save the character that has prop elements.
Currently, CTA3.03 is not support to save the character of the face have accessory.

Today I loaded a G3 character and wanted to change a nose sprite, which added a mustache and glasses to my character with the nose. That was easy in character creator, but when I saved the character it did not save with the sprite change, indeed going back to the stage after editing the changed sprite was missing too. The only way I have found to do this is to change the sprite at the first frame, without going to Character Creator. But I would like to save this character as a custom character with the sprite change. So, sprite replaced I tried to save it to custom from the stage (pressing + while in custom & with the changed character selected) & it went through the motions & added a character, but then when the new custom character is added to the scene, the sprite change is again gone. I know it's got to be something simple I am doing/not doing. BTW this is one of Gary Pye's characters, so Gary, if you have an idea what I am doing wrong, I'd appreciate it. 

My PC
====
OS: Windows 10 Pro x64
CPU: 4.00 gigahertz Intel Core i7-6700K
MB: Gigabyte Z170N-Gaming 5
RAM: 16GB DDR4 2133
HD: 2-2TB Western DigitalCaviar Black
VB: EVGA GTX 980
DirectX: 12


"Sure you can trust the government, ask any Indian."