You want the explorer background to be transparent , right ?
In the
Midnight Glass Nature Theme by ~MrGRiM01 on deviantART download folder, there is a folder named "Theme Optional Extras". An application named "Full glass.exe" is included there. Double click on it, check that whether it comes to your system trey . If full glass is present in your system trey, it is running then and you will see the explorer background in nice transparent.
Full glass.exe makes the explorer background transparent for the themes which have black background by default. If you dont found it, I am providing it for you.
By the way, if you dont use a theme with black explorer background, dont run full glass (right click on the systrey full glass icon and then click exit), coz it will make the explorer a bit hazy then