Per instance sprite customization let you define properties for each every copy of a sprite.
Class Each sprite belongs to a class.
Trigger key The trigger is a int value between 1-31. Sprite can either generate a trigger or be the recipient. The way that it works is that two sprite with the same trigger key are join whereas on trigger flip on the other.
Displayed in Sprites can be displayed or hidden based on the skill level chosen by the user.
attributes and trigger flip Sprite attributes and trigger flip is explained in Sprite Trigger.
The edit sprite button simply allows you to do Edit Sprite.
This is just a text string associated with this instance of the sprite. It can be retrieved though scripting using the Sprite:getString() function.