Оформил: DeeCo
Автор: http://www.swissdelphicenter.ch

// You can move the caret in a TRichEdit component by using this code : 

procedure RichEdit_MoveTo(RichEdit: TRichEdit; LineNumber, CharNumber: Word);
 begin
   RichEdit.SelStart := RichEdit.Perform(EM_LINEINDEX, LineNumber, 0) + CharNumber);
 end;

 procedure TForm1.Button1Click(Sender: TObject);
 begin
   RichEdit_MoveTo(RichEdit1,2,5);
   Application.ProcessMessages;
   RichEdit1.SetFocus;
 end;