I just deployed an update that fixes a few of the recently reported bugs:
* Proximity indicator circle now hides properly when deleting the block
* Proximity settings panel layout has been fixed (layout was broken when disabling "once" checkbox)
* Proximity once check didn't always reset properly when detecting particles
* Made no permission / not logged in indicator more obvious (flashes, plays sound when save fails), to hopefully prevent people from editing while not logged in and losing work.
* Fixed error when pasting in the sprite editor with an empty clipboard
You may need to clear your cache, since the lock icon in the "saving locked" indicator has changed