There is some confusion on the Coppermind on whether Sixthface is the name of the world (I seem to recall it was named ‘the cube’) or just one of the Faces of the world?
Furthermore, can you tell us something we don’t know about any of the Faces?
Ha. Not often I get questions about that particular story.
It's so unfinished that I haven't established, even for myself, all of the terminology.
So, do you have any plans to finish it one day?
It depends on a lot of factors. One is if there is interest for something a tad more ridiculous from readers. While it's not as off the wall as Alcatraz, that story is quite weird with a particularly specific kind of humor. If the Alcatraz re-releases do well, then perhaps there is room for something akin to them.