Hello!

I am searching for a way to extend core modules (in my case the link module) without changing the code - I would like to use this method with other modules too so I posted here. My idea is this:
I create a custom module which should use the link module, but it should change the way links are displayed. All I do is to copy the dnn_links.dnn for my module and change it from:
<control>
  <src>DesktopModules/Links/Links.ascx</src>
  <type>View</type>
  <helpurl>http://www.dotnetnuke.com/default.aspx?tabid=787</helpurl>
</control>

to

<control>
  <src>DesktopModules/MyCustomizedLinks/MyLinks.ascx</src>
  <type>View</type>
  <helpurl>http://www.dotnetnuke.com/default.aspx?tabid=787</helpurl>
</control>

Then in MyLinks.ascx.cs in the OnInit function I do this:
.....             
    Control ctrl = LoadControl("../../DesktopModules/Links/Links.ascx");
    objModule = (DotNetNuke.Modules.Links.Links)ctrl;
    if (objModule != null)
    {
        Controls.Add(objModule);
        objModule.ModuleConfiguration = ModuleConfiguration;
    }
....

It works - my module uses the link module.

BUT: I want to EXTEND the core Links.ascx.cs
So I tried this way:
I created I file called MyDerivedLinks.ascx.cs (with appropriate class) which inherits from DotNetNuke.Modules.Links.Links - there I could override a public function

Now I change MyLinks.ascx.cs to:#
.....             
    Control ctrl = LoadControl("../../DesktopModules/Links/Links.ascx");
    objModule = (MyCustomizedLinks.MyDerivedLinks)ctrl;
    if (objModule != null)
    {
        Controls.Add(objModule);
        objModule.ModuleConfiguration = ModuleConfiguration;
    }
....

And there comes my problem:

Error:
DotNetNuke.Services.Exceptions.ModuleLoadException: Unable to cast object of type 'ASP.desktopmodules_links_links_ascx' to type 'MyCustomizedLinks.MyDerivedLinks'.

Thank you!
Torres