Let me see if I can answer all of your points:
1. I can't help what WindowBlinds is doing, unfortunately. I am just setting up a standard, border-less window. If WB is causing an offset, I would investigate WB.
2. I'm not sure what you mean? The taskbar transparency doesn't work? It is supposed to change to not transparent when you mouse-over.
3. By task I assume you mean a window? Where does this thumbnail stay? Check your DisplayFusion Taskbar settings and make sure that you have "All taskbars show relevant windows" selected.
4. I did make some changes to the wallpaper randomizer, but nothing major.
5. Serial wallpaper changing is already in. It only works with local images, but just select "show images in alphabetical order" and you're all set.
Please correct me if I'm wrong, but the only issue still remaining from your list is the taskbar items not being removed correctly? Does it work with the new Beta 8? Thanks!