Sorry for not answering these sooner, every time I was going to I ended up with the lengthy and tedious task of updating tables etc.
What do play-offs mean exactly? I know we're going to have them, as all duels were played and 3 of us are in the second place, so what's going to happen with us 
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If there are two tied for a place, it's a simple duel between the two, with the winner going through.
If there are three tied for a place, it's a mini-round robin between the three, with each having a duel against the other two. In the possibility that there's some kind of rock-paper-scissors dynamic and the three are still tied, the process will be repeated (current workings, if someone has a better idea please suggest it since I can't think of one and haven't slept for about a day.)
Like Golradir said, it should all be posted once the Group Stage is over. Since the group stage is going to be ending at
about the same time I should be revising for some exams, there might be one or two delays.
After the frankly abysmal number of drop-outs, and some other concerns, I've recently been entertaining the notion that after ND3, I'll just run a persistent ND-Ladder (seeded initially with ND3 final results). Obviously I'll need to work out the basics (who can challenge whom when, how to handle inactivity and the myriad other challenges I'll probably have to steal the solutions to from from flust.) Once this ladder is up, I can then start running ND4, ND5 etc. etc. as relatively small single-elimination tournaments (probably 32 or 16 players) seeded from the top 16/32 players on the ladder.
I'd be interested in hearing criticism, suggestions or general thoughts regarding this.
