One way is enabling the "Decombine on..." options. This way, when you e.g. move your mouse pointer towards the taskbar item, it will expand, and will allow you to reorder/detach items.
Another way is using Taskbar Inspector, but that's less appealing.

Old versions can be found here:
https://www.dropbox.com/sh/mcbychsh0xc1dvu/8-Lj2sg3NP

But from your last screenshot, I don't understand what you're trying to achieve. You cannot drag within a combined group with the "Drag within/between groups using right mouse button" option. This option works only with the taskbar items, not with thumbnails.

To reorder thumbnails, you can use the "Thumbnails -> Drag to reorder" option, which is turned on on your screenshot. but you cannot use this option to detach an item from the group.

I can't reproduce it. Could you provide screenshots of:

• Your tweaker options.
• Your taskbar properties.
• The taskbar, where the issue can be seen.

Thanks.

Well, I get email notifications for the comments here :)
Unfortunately, I cannot say much without having a way to reproduce it. If you can find a scenario where it stops working, please let me know.
Also, disable_topmost=2 does two things: makes the taskbar non-topmost, and allows windows to be maximized beyond the taskbar. Which of these two features stop working?

Hi,
No, I have no idea as of why this happens. Are you using any extra customizing tools, such as Classic Shell?

It's not available in v4.5.9.2. I've just released v4.5.9.3, please try it.

A duplicate of http://tweaker.userecho.com/topic/534868-latest-update-shows-7-taskbar-tweaker-could-not-load-library-206/

I don't have update checking on

That's unexpected. So you disabled update checking, and you still experience crashes? Could you post a crash report?

Looks like a duplicate of http://tweaker.userecho.com/topic/534868-latest-update-shows-7-taskbar-tweaker-could-not-load-library-206/
Please try the beta version, which should fix the issue.