Interesting, thanks !

Given the limitations (zip only and performances), I don't know if trying to build something efficient using remote resources would be really doable, but at least now I know there is a possibility.

I tempted to try to automate certificate management using Acme4J.

I don't know when or even if I'll do it, but manually managing certificates sure is painful.

Great !

I'll update the FAQ and the download page so that users know they need a really recent version of Java.

Sure:

tom 'at' vaemendis 'dot' net

Another idea: try to update to the latest version of Java 8 (you are currently using 1.8.0_60, the latest is 1.8.0_92).

I'm not sure of it, but the missing library (javalcms) seems to have been embedded in recent versions only.

Managing permissions on subdirectories would have added too much complexity, both on code and user side.

It just wasn't worth the trouble.

Great !

Now if you understand why it works (like I said, I don't know much about nginx), let me know.

Argh, this problem should have been fixed in 1.10.1.

I don't know what went wrong, but until I do, you can try launching Ubooquity using the command line and adding the flag described in this comment.

Try these configurations (verbatim, slashes are important):

location /ubooquity/ {
    proxy_pass https://localhost:2202;
    proxy_set_header Host $host;
}

location /ubooquity/ {
    proxy_pass https://localhost:2202/ubooquity/;
    proxy_set_header Host $host;
}

My guess is that both of them will work.

I'd advise the same procedure.

But I don't know a thing about how QNAP Nas work.