Just in case anybody needs this. Almost every lockscreen/homescreen widget we install will mostly had its own wallpaper. The only way to change it is to ifile the wallpaper.png file in the theme. Quite troublesome if you ask me. Wallpaper JPEGifier which can be downloaded from cydia makes it much easier to change the wallpaper anytime you want. Just download it from cydia, after that edit the html file for the theme for the image to point to /var/mobile/Library/SpringBoard/Converted-LockBackground.jpg or HomeBackground.jpg Thereafter, choose a wallpaper in the settings, re-spring and volia, your wallpaper has been change! Quick and easy ever after!