Hey ronald, listen up!
"MarkerName" SetMarkerType "Empty" = HIDDEN :-X
"MarkerName" SetMarkerType "Flag" = FLASH IT
( ps. "Flag" or any other type, off course )
"Flag", "Flag1", "Dot", "Destroy", "Start", "End", "Warning",
"Join", "Pickup", "Unknown", "Marker", "Arrow", and any custom markers etc.