Deleting objects is possible; there's a macro object for that, "scenery remover" if I recall.
Spawning objects however is still not possible.
And no, deleted objects can't be respawned either, gone is gone.
There's only been one update to the Ring so far, a few months after it was launched, which did fix a lot of bugs and add a bunch of features. But that's almost two years ago now, and there've been no more updates to the Ring since.
In fact, there've slowly been features breaking down again since then. If anything, less is possible in the Ring now than there was a year ago.
