This function retrieves the distance of an element (start point) along a particular element set.
GetElementDistanceAlongSet (string DatabaseName, string SetName, int ElementIndex)
DatabaseName (character string). The full path name to the relevant database.
SetName (character string). The full name of the relevant set.
ElementIndex (integer). The relevant index of the element.
-9999998 (if there is an issue with the database file)
-9999999 (if there is an issue with the indexes)