C# Cast Class to Overridden Class
===

I have a class `Application` that I need to override with INotifyPropertyChanged events.  I have written the logic to override the original class and ended up creating `SuperApplication` 

I am pulling the data from a library though, and cannot change the loading logic.  I just need a way to get the data from the original class into my superClass.  I've tried things like `superClass = (SuperApplication)standardClass;` but it hasn't worked.

How would I go about doing this? 

If it helps, this is the code I'm using to override the original class:

    public class SuperCreditApplication : CreditApplication
    {
        public SuperCreditApplicant Applicant { get; set; }
        public SuperCreditApplicant CoApplicant { get; set; }
    }

    public class SuperCreditApplicant : CreditApplicant
    {
        public SuperProspect Prospect { get; set; }
    }

    public class SuperProspect : Prospect, INotifyPropertyChanged
    {
        public State DriverLicenseState
        {
            get
            {
                return DriverLicenseState;
            }
            set
            {
                DriverLicenseState = value;
                OnPropertyChanged("DriverLicenseState");
            }
        }

        public event PropertyChangedEventHandler PropertyChanged;
        private void OnPropertyChanged(string propertyName)
        {
            if (PropertyChanged != null)
            {
                PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
            }
        }
    }