That last one has happened to me as well 😉
But it’s not Blender that’s the problem in your case, but your understanding (or lack of it) of how it works.
For instance, Blender will, by default Render what’s in the Compositor and what’s in the Sequencer (if there is anything there),. You can disable that here:

Other problems you might have encountered can most likely also be explained.
It’s usually just human error, so that ‘proves’ that you’re not a bot, or so.