Not if activated by the Activation Device. The primary difference between a group and a scene is that the intent of the group is that the devices follow the Activator Device for their settings, and with a a scene that they follow the settings in the table. That option controls what happens when ON is commanded to the Activator Device. With it deselected, there is no difference between the group and a scene as pertains to commanding ON to the Activator Device. The difference between the two would only arise when commanding the Activator Device with some other commands, such as setLevel, setColorTemperature, or setColor.
Room Lights automatically selects the appropriate Activator Device based on the capabilities of the devices to be automated. Another use for the Activator is to be used with Voice Assistants. If you want to be able to say, "Alexa, set Living Room to 40 percent", where "Living Room" is the Activator Device, then it has be a device that can respond to setLevel (etc.). See this post: Room Lights: Scenes, Groups & Voice Assistants
Those different drivers have the fairly obvious capabilities, except for "Room Lights Activator" that has all of the capabilities. Changing the driver usually isn't necessary.
Yes, this is correct. The app chooses the appropriate driver IN CASE you want to control them with a Voice Assistant. Room Lights doesn't really know your intent. On the other hand, if all you have are switches and dimmers, there would be no point in creating a device that can set colors.
