A Long expression that indicates the index of the skin being removed.
Use the Remove method to remove a specific skin. The
identifier of the skin being removed should be the same as when the skin was
added using the Add method. Use the Clear
method to clear all skins from the control. If you need to remove the skin
appearance from a part of the control you need to reset the last 7 bits in the
high significant byte of the color being applied to the background's part.