Adding Extra Steps To A Create User Wizard Asp.net (c#)

 Hi,
 Apologies in advance if you get confused by reading this.... I am trying to create an additional step in the Create Wizard User Control that is provided by ASP.net. The additional step that I want to add will come after a user will create their username, password, email etc. The information which I want to save in the extra step are details such as firstname, lastname, address, height, weight etc. (I am creating an online weight management system for dieticians).
When I  run through the application, the username, password etc save perfectly to the database, but nothing happens with the other "personal information". There are no errors thrown so I don't know where the problem is coming from.
I have included the code below as I have it:
The code behind the Register.aspx file is as follows:
 <asp:SqlDataSource ID="InsertExtraInfo" runat="server" ConnectionString="<%$ ConnectionStrings:ASPNETDBConnectionString1 %>"
InsertCommand="INSERT INTO [aspnet_UserInformation] ([first_name], [surname], [address1], [address2], [city], [country], [number], [height], [weight]) VALUES (@txtFirstName, @txtSurname, @txtAddress1, @txtAddress2, @txtCity, @txtCountry, @txtNumber, @txtHeight, @txtWeight)"
ProviderName="<%$ ConnectionStrings:ASPNETDBConnectionString1.ProviderName %>">
<InsertParameters>
<asp:ControlParameter Name="txtFirstName" Type="String" ControlID="txtFirstName" PropertyName="Text" />
<asp:ControlParameter Name="txtSurname" Type="String" ControlID="txtSurname" PropertyName="Text" />
<asp:ControlParameter Name="txtAddress1" Type="String" ControlID="txtAddress1" PropertyName="Text" />
<asp:ControlParameter Name="txtAddress2" Type="String" ControlID="txtAddress2" PropertyName="Text" />
<asp:ControlParameter Name="txtCity" Type="String" ControlID="txtCity" PropertyName="Text" />
<asp:ControlParameter Name="txtCountry" Type="String" ControlID="txtCountry" PropertyName="Text" />
<asp:ControlParameter Name="txtNumber" Type="String" ControlID="txtNumber" PropertyName="Text" />
<asp:ControlParameter Name="txtHeight" Type="String" ControlID="txtHeight" PropertyName="Text" />
<asp:ControlParameter Name="txtWeight" Type="String" ControlID="txtWeight" PropertyName="Text" />
</InsertParameters>

</asp:SqlDataSource>


 Then the code I have behind the Register.aspx.cs page is:
 
protected void CreateUserWizard1_CreatedUser(object sender, EventArgs e)
    {
        TextBox UserName = (TextBox)CreateUserWizard1.FindControl("UserName");
        SqlDataSource DataSource = (SqlDataSource)CreateUserWizard1.FindControl("InsertExtraInfo");
       

        MembershipUser User = Membership.GetUser(UserName.Text);
        //object UserGUID = User.ProviderUserKey;

        DataSource.InsertParameters.Add("UserId", UserGUID.ToString());
        DataSource.Insert();
    }
 
I know there is a problem with the code on the aspx.cs page but I cant figure it out. I need the username / password information to relate to the personal details information. I know I have to create a foreign key in the asp_UserInformation table that will link to the username in the asp_Membership (where all the username / password info is stored)
 
Any help will do, I'm almost in tears here!!!
The Spud