I downloaded latest HoloEveryWhere
Then Import from existing code --> library folder --> Properties --> isLibrary --> Ok
Then Import from existing code --> Demo folder --> Properties --> addLibrary --> Library
And in demo i have i errors, see in images


Try removing the imports in the second image and then clean and rebuild.
Also ensure that Inside the SlidingMenu library, that the class SlidingFragmentActivity extends SherlockFragmentActivity. Check the link below for more information on this. This is the only problem I could think of for the getSupportActionBar() without seeing the actual errors.
Editing SlidingMenu
EDIT:
It may also be worth checking that your project is referencing the correct libraries. Right click on your example project in the package explorer -> Properties, then select android and check that in the library section that there are references to the SlidingMenu and ActionBarSherlock libraries.