Problem Installation of Logic Pro 9....

Spent some time installing Logic Pro 9 this morning. Everything went swimmingly until the last Install Box that says " Installing Logic Pro 9 and Mainstage Additional Content " hove into view. Nothing happened. And several hours later it's still not happening ! The box is sitting there immovably mocking me. Is that it ? Does anyone know how to kick it into action ? Also, surprisingly, I haven't been asked to pay yet.....