Open Drive Cloud Storage

I can see Open Drive in the left panel and can access files on it. But when I try to drop files on it (add files to the cloud storage) it puts up the 'no access' icon. So I am unable to add files to my Open Drive cloud storage using Directory Opus.

Yet using Windows Explorer it works fine and as you would expect, just like any other drive or network drive on my computer. Why is this? Am I doing something wrong?

If you drag from Explorer to Opus, with Open Drive in Opus, does that work?

What about in the other direction, with Open Drive in Explorer and dragging from Opus?

I have exactly the same problem. Yes it will copy either way if I involve Windows Explorer.

What I really want to do is use the sync on Opus like I do to my NAS. It is happy to copy from Open Drive but not to Open Drive. Open Drive does not appear in the "Select Destination" box. I thought I would be clever and pretend to sync from Open Drive to my computer and then use the swap arrows to reverse the direction. This was OK on compare (it correctly worked out how many files and directories needed syncing) but when i pressed 'Synchronise' the "Select Destination@ box popped up again of course Open Drive does not appear in that (strangely OneDrive and BT do!!).

Any help much appreciated.