As of right now several parts of the main questline are glitched. Giving the book to the shaman elder bugs out as his dialogue ends and the animation of him opening the book and hermeas mora grabbing him does not play out.
Third bug seen was upon reaching the final part of at the summit of apoc, where you fight Miraak; If you kill him before each dragon is absorbed he reappears in a permanant ethereal form. If u manage to drop him at least below 30% health but keeping him above 10% u will allow his animation to play out correctly, however even after the final dragon is dead and absorbed and you go to finish him off once and for all, he will bug out and appear below the central pool platform. So far bethesda has taken no regards to fixing any of these bugs and thus far the unofficial dragonborn patch has only hotfixed bugs that were occuring based on the original unofficial skyrim patch. That being said neither bethesda nor the unofficial patch team has made any advancement towards hotfixing the current game breaking bugs players have seen in the new dragonborn DLC thus far.
I'm really hoping they fix this soon as i've also read of multitude of other bugs being reported, such as not being able to ride the dragon to Miraaks location, though from views and posts it looks like its a minor bug based on you having dragon souls or not so be sure you do before using the book and venturing to the final part of the last part of the main quest (at the summit of apoc).
For those wanting to complete the part of the elevator thats bug, type tcl to toggle clipping and just run to the top and talk to Neloth. NOTE: Your follower may bug out and continue to try and return to neloths tower where the elevator lift is, (having your follower stay at a location far away is advised) and may not even venture outside. To fix this you must target your follower and then travel at least 100 yards from his place, and type moveto player in your command line and have them engage in active combat. This fixed it for me. Also if you would like to finish the part where the shaman bugs out. type out Setstage dlcmq05 1000 and then add the player shout required for your quest stage which should be the third word of bend will that hermeas mora normally teaches you. (Btw shaman doesn't die at this point and he will have taken your book if you talked to him before he bugs out in the broken animation, so if you would like the book back i suggest adding it back via player.additem)
player.teachword xx0179db where xx is you replace that with whatever dragonborn is in your load order under data files. For example mine was 04, however yours might be 03 or 02 if you havent gotten dawnguard or hearthfire.