You should be able to upload images on localhost. Can you provide o more details on the problem, did you get an error? please describe in detail the difference between uploading on local host and on remote.
when logged in using the super user account (the account you set up during the PCMS installation) the header section will include a manage users link, see attached screen shot.
If you create an admin user, they will not be able to mange the users in the site, only the super admin can add new users.
The problem with the menu is that it is not inside the outwrapper div