I've just tested things again and am not able to reproduce any issues.
A couple of things to note (perhaps my title "Drag Anywhere" is too broad):
1. You CANNOT drag tasks INTO Smart Queues. When viewing tasks in a Smart Queue you can drag it to a regular queue are a queue shared with you.
2. You CANNOT drag tasks into queues that are shared with you in "view only" mode. Only "collaborative" shared queues will accept your tasks.
3. You CANNOT drag a task into the queue it is already in. So if you are viewing a Smart Queue and try to drag a task into it's existing queue nothing will happen.
Logout and login to ensure you have the latest version of the app (it should say "New: Drag Anywhere" in red at the top right when logged in)
When you drag a task over a valid queue does the name turn white like it should accept the task? If you drop it, does it go to the queue or just revert back to its position? Or does the queue name not even turn white when hovering over it?
-Cameron