Custom menus and widgets are unrelated. If any widgets do not appear in your sidebar then look for them in the Inactive Widgets box and reinstall them in your sidebar > Appearance > Widgets > Inactive Widgets
1.You add the Categories you want to display and arrange them in the order you want.
2. Then you add and drop and drag the sub-categories below the appropriate Categories.
3. You add the Pages you want to display and arrange them in the order you want.
4. Then you add and drop and drag the sub-pages (child pages) below the appropriate parent Pages.
5. You add the custom links you want to display and arrange them in the order you want.
6. When you have everything arranged in the menu that you want you save the menu.
7. Go to the “theme location” module at upper left on the menu page. Select your custom menu name from the pull-down labeled “primary location.” Click the save button in that module.
8. Refresh your browser so that it isn’t possibly pulling a cached page, and view your new custom menu with Parent pages and dropdowns to sub-pages, and Categories with dropdowns to subcategories, and Custom Links.
Troubleshooting – My menu isn’t appearing
Go to the custom menu page in the dashboard Apearance > Menus and in the “theme location” module at upper left select your custom menu from the pulldown and then click “save”.