No, that's what themes are for

Duplicate.

http://tweaker.userecho.com/topic/166060-show-labels-on-hoveractive-window-for-non-grouped-items/

A screen recording of what?

I can imagine what a 7 seconds hang looks like :)

What you can do is find a way to reliably reproduce the issue. If you think it might be caused by XWindows Dock, experiment with it being on/off.

I don't think it's the tweaker's fault. It's auto-hide functionality is quite straightforward, there's not much that can go wrong.

I was talking about Windows' taskbar properties, i.e. right click -> Properties.

From the buggy behavior, I guess it is "Combine when taskbar is full".

The thing is combining options weren't designed to work with this option.

With "Combine when taskbar is full" Windows decides when to combine/decombine groups, according to the available free space. It doesn't expect other apps to play with the combining.

So either switch to "Never combine", or disable the decombining options.