Create a Drow Down Menu New Feature - repost

Our CMS adds new pages using Horizontal Top Nav Menu system that it does not escale. We need to allow users to add more pages as a Drop down menu options so that the site number of pages can grow if needed. WHAT WE NEED: 1-) Add a Drop down menu options.. 2-) Create a warming message stating that reads (below) if they try to add more than 6 pages. "you have exceeded the number of pages that can be added. Use the create drop down option instead to add more pages. 3-) Test it make sure that it works. 4-) resolve any bugs found. OBS: See screenshots attached. By the Way our CMS is written in PHP and uses msql. NOTE: You will be given higher priority if you can make this into a a plugin that can be easily added to any other mock ups we have.