If you want to work with tweak settings, register the action in the configs and in the PApplicationPool. Enter the action name in the config. In your implementation, call registerAction using an instance of the PApplicationPool. When programming with Visual Basic, call application.commands.add("<name of action>"). After registering the action, you can set other properties (e.g. icon path, ...) The difference to earlier versions is that you do not register menus or toolbars in the application. The registerToolbar and registerMenu steps are carried out using entries in menuvisibility-config and menustructure-config. Actions also have the additional property autoRegistered. If you want to check whether an action already exists, check the value of this property. If "true", the action is registered. Otherwise the value is "false". The query as to whether an action already exists will always return "true". The reason for this is that "Tweak" registers all actions from menuvisibility-config like a prototype.