Ok, so. I fixed this. . . For me at least. Just recently started working on a new mod, timed perfectly for Beth to get creative and blow up the CK again. Noticed today that -nothing- papyrus could be generated after this lovely update. Then I looked here, saw this, remembered an old backup I made of -all- the old niller source documents for some silly reason, merged it in my existing source folder, shut off CK cloud via steam updating and bingo--script compilation working like it always did. Now the concern is can I share the old source files for people with the same problem without getting into trouble. In any event though, it's a fix :D