How to install MIUI MiLocker theme......
- Download APK file from here
- Download .mtz file.
- Copy .mtz file to "sdcard/MIUI/theme".
- Then Apply the Lock screen.
If you want to add another background, then just copy wallpaper to "sdcard/MIUI/wallpaper". But when you copy a wallpaper, remove the extension of the wallpaper.
For example : nature.png -> Remove ".png" from this file then copy to wallpaper folder.