unfortunately I'm not aware of any plans to change this behavior.
As said, it's related to the ONTAP API behavior so not even OCUM's fault.
I just made a quick test with OCUM 6.3 and other than described above I noticed that it's not even possible to restore a single file from a directory with more than 995 entries even if you know its exact path and name.
That's definitely not the behavior I'd have expected.
"Previous versions" directly from Windows Explorer is working fine though. As you mentioned that in the header as well, would that be a possibility for you?
I understand though it can only restore files from local SnapShots and not from SnapMirror or SnapVault destinations, so that might be a drawback.
If you need that feature in OCUM I encourage you to talk to your NetApp representative(s) in order to help you articulate your use case and present it to Product Management.
As said - it's generally working as designed, so would be a new feature request.
Kind regards, Niels