RMC_COSymbol function.
Add a CustomObject Symbol or alter an existing CustomObject.
Syntax
	nResult (LONG) = RMC_COSymbol( ByVal nCtrlId (LONG), ByVal nCOIndex (LONG), ByVal nXCenter (LONG), ByVal nYCenter (LONG), ByVal nStyle (LONG), ByVal nColor (LONG), )
Parameter
	nCtrlId (LONG)
		Unique ID of the chart control.
	nCOIndex (LONG)
		Index of the CustomObject. If a CustomObject with this index exists, it will be overwritten, if not, a new CustomOject will be created.
	nXCenter (LONG)
		X center of the Symbol within the chart (in pixel).
	nYCenter (LONG)
		Y center of the Symbol within the chart (in pixel).
	nYCenter (LONG)
		Y center of the Symbol within the chart (in pixel).
	nStyle (LONG)
		Style for the Symbol, defined as a symobl constant. If omitted or 0: RMC_SYMBOL_DIAMOND
	Color (LONG)
		Color for the Symbol as a Color...constant or as a RGB value. If omitted or 0: ColorBlue
Return value
	0
		No error, function succeeded.
	RMC_ERROR_CTRLID
		Wrong control ID (0 or no chart with this control ID was found).
	RMC_ERROR_CUSTOMINDEX
		Parameter nCOIndex is not valid (either 0 or it exceeds the maximum number of CustomObjects (200).
	RMC_ERROR_ALLOC
		Error while allocating memory for the CustomObject.