How to add checkbox to first page in innosetup

How do i add the check box to a particular page in Innosetup? I want the check box to be shown only in the first page or ReadyToInstall page? I wrote code to add check box to wizardForm but I see the check box is in every other page. I see we have to specify which page but i tried several options and it's just not happening. I believe this should be simple but i'm totally lost.

Also, from the screenshot below, my checkbox label seems to have some highlighted background. how can i get rid of this background and add border to check box in light color?

var
  EnableRMCheckBox: TNewCheckBox; 

procedure InitializeWizard;
  begin
    EnableRMCheckBox := TNewCheckBox.Create(WizardForm);
    EnableRMCheckBox.Parent := WizardForm;
    EnableRMCheckBox.Top := 120;
    EnableRMCheckBox.Left := 87;
    EnableRMCheckBox.Width := 180;
    EnableRMCheckBox.Caption := 'Enable RM';  
  end;