That's actually possible with the option "Ctrl+Win+Tab (Windows 7)". I'll rename it in the next version to make it clearer.

At this time, Windows 10 builds newer than build 10240 are not supported.

A is already possible with the option "Don't group pinned items".

B and C are not great due to the reasons you've mentioned.

The complaint from the user (my parents :)) was...

Feedback from non-tech-savvy users is sometimes the best kind of feedback :)

I suggest you to try using one of the two options I mentioned:

1. "When not grouping, place new items next to the existing ones".

2. "Don't group pinned items".

Try one of a time. The result will be different. See what your parents like most. Feel free to share the result :)

Closing as a NOT A BUG, because it is not a bug :)

This is by design. Similar behavior can be seen without the tweaker:

[pinned Firefox] [pinned app X] on task bar.

1. open Firefox = [Firefox window 1] [pinned app X]
2. move Firefox = [pinned app X] [Firefox window 1]

3. close Firefox = [pinned app X] [pinned Firefox]

What behavior would you expect to get in your example?

If you'd like to have the Firefox windows in one location, you might want to use the option "When not grouping, place new items next to the existing ones".

Looks like a bug of Windows 10. A tooltip is shown on Windows 7.

I assume that you're using Windows 10, right?

Please try the latest beta version:
http://rammichael.com/7-taskbar-tweaker#download

The "Auto-hide the Taskbar" option does exactly what you want, as far as I understand your request. The tweaker's option disable_topmost=2 was mostly designed for non-auto-hide taskbars.

Can you please clarify what's wrong with the "Auto-hide the Taskbar" option? Is it the thin line when the taskbar is hidden?

In some cases (especially with a multirow taskbar), there are issues when labels for some, or all, of the items are hidden. Perhaps that's one of these issues. Unfortunately, that's very difficult to fix, and because the issue is quite rare and specific, I don't plan to investigate it in the near future, sorry.

It's a known bug, and is not related to the tweaker.

For a solution, see:

http://superuser.com/questions/61833/windows-7-taskbar-icon-highlight-sticks