Good point, this is a nice approach, too. Based on this, I update the list of existing customization options:
- User downloads standard Slicer installer and installs extensions manually.
- Custom installers (have custom application name, some additional extensions are bundled, some modules are excluded) - this can be built without modifying anything in Slicer source code, just by tuning CMake options (except resources). No extension manager access.
- CustomSlicerGenerator: It works but it has two serious limitations (no installer is available, just a zip file; resources, such as any icons and bitmaps shown in the application are not customizable - except application icon and splash screen).
- Custom launcher: Shortcut in the Start menu (Windows) or Application directory (MaxOSX) that starts Slicer, jumping right into a slicelet (module with a simplified user interface). It uses standard Slicer installation.
All these options have some merits. I guess we just need to decide if we want to promote one of these methods to be an officially supported, widely advertised solution for distributing customized Slicer versions.