Reading and Writing Components to files

Can somebody show me the proper way to use ReadComponentResFile?
I am trying to load and show a form at runtime.  I used
WriteComponentResFile to generate a RES file, but cannot seem to get
ReadComponentResFile to act properly.

I create the res file like this where sbxPage is a TScrollBox with
descendant components.  This should generate a RES file that has sbxPage
and all its descendants.
procedure TfrmFormWriter.Button1Click(Sender: TObject);
  WriteComponentResFile( edtFormFile.Text, sbxPage );
end; //]

I try to read it back in like this: where sbxPage is an empty
TScrollBox, but nothing noticible happens.  sbxPage.ComponentCount is
still 0 after the call to ReadComponentResFile.
procedure TfrmFormReader.Button1Click(Sender: TObject);
  ReadComponentResFile( edtFormFile.Text, sbxPage );
end; //]

What am I not doing right?