Window

Window > Next

This command switches to next opened image.

Window > Previous

This command switches to previous opened image.

Window > Close All

This command closes all opened documents in NIS-Elements.

Window > Close All but Current

This command closes all opened documents, but keeps the current one opened.

Window > Close

Equals the File > Close command.

Window > [Opened file]

This command brings the selected image into focus (makes it active).