After installing your plugin from the zip submitted to the plugins directory, I ended up with dirs permissions like drwx-w---- (root, classes, db, lang). Together with how files ownership is set, this prevents the plugin from being installed.
Please make sure the files and dirs in the zip package give the group the rx permissions.
In my case, I had to run chmod -R g=rX autogroup/
After installing your plugin from the zip submitted to the plugins directory, I ended up with dirs permissions like
drwx-w----
(root, classes, db, lang). Together with how files ownership is set, this prevents the plugin from being installed. Please make sure the files and dirs in the zip package give the group therx
permissions. In my case, I had to runchmod -R g=rX autogroup/