Helmut- What's so confusing? Xnview should simply start up with the same menus, toolbars, etc as it has when you're viewing an image. Most other image viewers/editors work this way (and the ones that don't completely work this way, still don't change the toolbar).
If there is no image open, then the image based functions in the meus are disabled, but they remain in the same positions and none disappear. Look at uniview, irfanview, image analyzer, or photo filtre (just to name a few). Look at them without an open image, look at them with an open image. Aside from some menu items being greyed out/disabled, you won't see any difference.
You can start XnView in viewer mode by double-clicking on an image.
No offense, but that was a dumb statement. I don't want to launch an image when I open xnview. Not only would that be pointless most of the time (since I'm not working on an existing image), it is also much more of a pain to go into your folders and hop around looking for the image you want than it is to simply fire up a program, especially if the image you want is in the same directory as the last image you opened.
Most of the time, I either fire up xnview and paste the clipboard, or open an image in the same folder (or near the same folder) as the last one I opened. In both cases, going through the hassle of navigating to and then clicking on an image just to launch the program would be beyond pointless.
I don't know why the basic vs viewer mode thing bugs me so much, it's just that things which make no sense really get under my skin.
Now, some might argue that basic mode is good for when you want to aquire an image from a camera or scanner, but as soon as you open the first image, it switches to viewer mode and you lose that advantage. Additionally, all the things in the basic mode toolbar can easily be added to the viewer mode one, thereby making it just as easy to aquire an image from viewer mode as from basic mode.
If basic mode can't be done away with, I think there should at least be an option to launch the viewer at startup the same way you can choose to always launch the browser at startup.