Displays each frame in your animation as a thumbnail. Each thumbnail frame also displays the time delay of the frame. There are also shortcut buttons on the Frame Panel for quick access to commands like Play Animation. To change the position of the Frame just drag it to a new position.

Click "New blank frame" Command in "frame" menu to insert new frame at the end of animation,

Click "Remove" command to delete the selected frame.

Change Color count

Color count is  the maximum color count of this frame 's color palette. This can be used to shrink gifs. But, as colors are taken away, the image quality tends to degrade. The goal with color reduction is to find a balance between effective compression and image quality.