I have successfully installed Cytoscape.
Version: 3.8.2
Java: 11.0.6 by AdoptOpenJDK
Java Home: /Applications/Cytoscape_v3.8.2/.install4j/jre.bundle/Contents/Home
OS: Mac OS X 10.15.6 - x86_64
I have successfully installed several apps.
However, only one of the apps JGF App shows in App drop down menu, none of the other apps seem present/active. For example, gexf-app should allow Cytoscape to import that format of file but neither 'File/Open' or 'File Import' recognize the file type.
Having read the docs, many file types are supported (seemingly) for import. However I have had no success in importing files which is arguably the most important to me at the moment.
How can I make the installed apps work or what may be preventing them from doing so?
Note: I this unanswered stackexchange question seems related.
My guess is that one of the apps you installed is crashing on startup and preventing the other apps from starting. I would start by disabling "JGF App" and "gexf-app" and see if the other apps all come up.
Looking at the list of apps, you won't see them in the apps menu, though -- look in the tools menu for "Merge" and "Analyze Network". Then, you can enable gexf-app and see if it starts up (if it doesn't, you should see an indicator in the lower left-hand corner of Cytoscape). If you click it, it will give you a little more information about what happened. If that starts up fine, you can try to enable "JGF App".