Hover Effects Explained:

Hover effects are what we call Mouse Over events. These are created by specifying either a hover color or creating a hover image to be applied to a tile upon mouse over.  Hover effects are valid for both tiles and menu items. Each section describes their usage. Additionally within those elements, you may specify the hover effect color for the text or label.

General Use:

Tiles that use only "internal tile colors" will display a color effect determined by the color specified in the General Configuration Dialog.

You may create special hover effect textures for tiles and assign them to the selected tiles by SHIFT+Dragging the hover texture onto the desired tile. Hover textures may be differing sizes than the "non-hover" texture.  Tiles without a custom image for the hover effect will display a color effect determined by the color specified in the General Configuration Dialog.

You may use animated .GIF files for Hover Effect images.
   NOTE: Tile labels will not be displayed on .GIF Hover Effects.