Try to use the following code and then use separate string items in the Run command.
td.Actions.Add(new ExecAction("myprogram.exe", "$(Arg0),$(Arg1),$(Arg2)")); task.Run("A", "B", "C");
Try to use the following code and then use separate string items in the Run command.
td.Actions.Add(new ExecAction("myprogram.exe", "$(Arg0),$(Arg1),$(Arg2)")); task.Run("A", "B", "C");