[xwiki-users] Editing an Application result in errors even when making no changes

Hi everyone, I recently tried to install a few applications onto my XWiki 8.4.2 instance, some of them (namely, Idea Application & Task Application) get this strange error whenever I tried to click Edit and just click Next to explorer the feature: the main screen will display some kind of exception about velocity macro and Space (I am sure you can reproduce this to see the details). Also, in the Application left navigation, application name will change to some kind of id/reference (e.g. ideas.app.title, TaskManager.panels.name). So, I have a few questions: 1. It doesn't seem natural to me that a user with role of normal user can Edit an Application. So what does it mean by "Editing an Application"? And why would it be normal to allow a user (non-admin) to edit an Application? 2. I am guessing Editing an application is some kind of administrative activities. If so, is there any documentation regarding Applications administration in XWiki? I found this: http://platform.xwiki.org/xwiki/bin/view/Features/Applications? but it covers only Installing and (a bit of) Usage. It references other documentation for Development of Application or XWiki itself but not administration. Thanks, Zoom