Could someone give me a way to see the custom controls of the project in Design mode?

For example when i open the pages\accessmasks.ascx in design mode i get what you can see in the attached image

I can't understand why PageLinks is rendered yet AdminMenu is not!

When i compile the project i get XHTML errors, for example in borads.ascx there is '

And why are there so many controls without the ID ? ( ) visual studio designer is complaining about this!

thank you in advance