I can't seem to change my lockscreen wallpaper on my Galaxy S3 Mini.
I go into
Settings > Display > Wallpaper > Lockscreen, and a popup appears where I select
Gallery. Then, I go to my wallpapers folder and select a picture. It appears with an orange box that you can resize and I tap on
Save. Presumably, it should now be set as the lockscreen wallpaper, but it does not actually have any effect.