I have updated the object Elev Marker JAM8. You can automatically display the elevation to Sea Level, as well as Project Zero. There is also an option for a break point when the symbol needs to bend.
In order to use Sea Level, select it in the Reference Level parameter. You must have your '1st Reference Level' set properly in Options -> Preferences -> Working Units and Levels.
To show a bend in the symbol, set the Break Point parameter to greater than 0. The height of the bend comes from the Height parameter. When Break Point=0, the Height is ignored.