The default location of user files is hard-coded into the Pydio app, and cannot be changed through the web interface[edit: this may be possible through the web interface at Settings > Workspaces > Common Files, and Settings > Workspaces > My Files. Try changing the file locations here first when logged in as an admin user]. You can change the location of your shares, but if you want to use Pydio to manage user data then you might want to move the default directories to a different location on your drive. For this example I will move the default file locations to a new Amahi share.