Your comments

Is your goal to have these custom groups (e.g. Calculator + Notepad) temporarily, or do you want them to be grouped every time you launch them?
If it's the former, I don't understand your statement about having to "exclude" every application. Can you please clarify what you mean?
Disable it globally, and enable it selectively. Unless I'm missing your point?

Похожий вопрос был тут:
http://rammichael.com/7-taskbar-tweaker/comment-page-17#comment-3660
Ошибка 102 говорит о том, что файлы программы из разных версий. Переустановите программу, должно помочь.
Yes, that's also what happens when you use the built in Windows feature:


Because the tweaker uses the same mechanism, you get the same behavior.
You cannot assign multiple hotkey actions to the same key.
The option to restore all items of a group is available for testing in v4.5.10.6 beta.
I could reproduce it. Should be fixed in v4.5.10.6 beta, please try it.
If you have the taskbar set to combine [...] you can right click you can choose to "Restore all windows"
Hmm, that may make it easier to implement the option in the tweaker. I'll look at it when I have time.

Also, iIt would be great to have an option to disable automatic grouping (by app ID's), allowing only manual grouping.

That's already possible with Taskbar Inspector, or with the Drag within/between groups using right mouse button option.