Good news!
MeizuCenter Pre-Alpha 7
What's new?
I added a new tab 'Wallpapers'.
You can simply check the wallpaper should be added at the Meizu.
Then click the button 'Add selected wallpapers to removable device'.
Bling!, the wallpapers are there.
edit:
Forgot to say: If you only select a name of a wallpaper, there's a preview of it!
It's worth testing!