With help from Greer, PJ and Hearts_blood, I believe that I've figured it out! Knock wood and pending final tests by volunteers — it doesn't work precisely the same when the collection's owner submits — I believe that the issue has been that the "moderated" setting conflicts with the "unrevealed" and "anonymous" settings. That is, when a collection is "moderated," stories submitted to it are visible all over the AO3 except in the collection itself, not veiled as "mystery stories," until the collection accepts them. So the solutions in need of testing are to either (1) set the collection "unmoderated" or (2) sign up each player as a "member" of the collection. Neither is hard! Well, now that I know...
(As a side note, FKFicFest won't use the AO3's automated matching system this year. I'm aiming rather just to consolidate posting and feedback for writers, consolidate queue management for me, enable MOBI downloads for e-reader users, and duck technical difficulties like LJ's DDOS firestorm last year. Stories will still be announced on LJ/DW (and forkni-l, for that matter), just not posted there. And I'd be able to release stories in a snap on AO3 first thing on waking up, even if I didn't have time to post the LJ/DW/forkni-l announcements until evening.)
Again, I have AO3 invitations for any and all FKFicFest writers, beta-readers and groupies who do not already have AO3 accounts. No one will be left behind! (If someone loathes and shuns the AO3 for some reason, she can post to LJ or DW, as before; we'll work it out. See how easy-going a mod I can be? I know; I'm shocked, too. ~grin~ Need sleep...)
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