There is no need to post the same issue several times in this forum, because it only wastes the limited resources of the volunteers who try to answer your questions. So please stick to the one created under the Zimbra category. I will close this one for you in the meantime.
It seems that you waited to upgrade your installation until the Zimbra Drive app support for NC 18 has been added, but I have the impression that you haven’t checked for any know issues of the app in advance 
I cannot tell you if the problem has been solved in the app itself, but at least a work around has been posted here: