Right-clicking on a frame in the Frame Gallery opens a pop-up menu which allows you to operate on the frame. The menu contains the following options:

New Frame  Identical to the New Button.

Copy Frame  Identical to the Copy Button.

Delete Frame  Identical to the Delete Button.

Preview Frame Identical to Preview Button.

Frame Properties Opens the Animation Properties dialog box.

Show Frame  Includes the frame in the animation. Deselecting this item means the frame will not appear in the animation.