Have you checked the IDE preferences and made sure it's pointed to the right path where the sketches and libraries are located? I only ask because I too keep my sketches and third party libraries somewhere other than the default path. But once set, when I install a new version of the IDE it picks up my preferences and I don't have to tell it each time where they are.
I would think if it had a bug, more people would be pointing it out.
I'd say get rid of all the preferences files. You may have uninstalled it, but it doesn't get rid of the preferences.txt file (on Windows) as that's in the user's AppData folder. Reinstalling the IDE won't overwrite that file either. You have to it manually.
error: 'time_t' does not name a type
Can you move the offending library .h, .c and whatever else is needed, into your user folder and get it to compile ?I mean, move the files away from the default folders into your personal arduino files folder ?
I forgot that there are actually three different libraries in subfolders that need to be moved up to the main folder.