Minimap Icon Background

Use this image in the "Minimap Icon Background" field under the Actor of a unit that you want to have a custom minimap icon on, along with a button icon in the "Minimap Icon Field", Then Scale the Images accordingly with the "Minimap Icon Background Scale" and "Minimap Icon Scale".

Here is a Tutorial on how to use this Asset

http://www.sc2mapster.com/forums/resources/tutorials/45097-data-custom-minimap-icons-in-under-5-minutes/#p1