Basically the title; everything I try results in a failure, and the CK crashes every single time I select the "Duplicate World Space" option; I've tried duplicating it in TESEDIT, and got nowhere, since I can only make over-rides, not new-records, apparently...

So, I'm at a total loss.

Short answer...No.

With TES5Edit, sure. You'd have to doctor the plugin a bunch though as, once the CK loads it, there will be numerous duplicate EditorIDs/erroneous reference data.