At the beginning let me say this: gtk-gnutella is not meant to be super-secure. If you run it, you do at your own risk.

... of course if we find a bug, we try to fix it.

Having said that... well... people should not have access to your filesystem at all. All that should have access to are the files that gtk-gnutella has index from the directories you told it to look in. Gtk-gnutella does not support a host-browsing, meaning that other people shouldn't be able to get a complete list of the files you are sharing.

Currently there is no way to actually see in the gui which files are indexed... but you can see the total size and number of files in your shared files library.

If you feel up to it, feel free to contribute a patch to browse the shared files library in the gui.