Well, that’s embarrassing. A little tweak to my dark matter model resulted in a leaderboard score in the top 10. The only problem is that the contest closed about an hour ago.
I ran this final prediction earlier today but then simply forgot to go back to it and submit!! On the bright side, I learned a lot of really interesting things about gravitational lensing and had a tonne of fun doing it. I’ll probably write a post-mortem sometime in the next few days, but for now I’m just kicking myself.
bayesianbiologist 
Congrats. This was a tough (but fun) competition. I’m curious, how correlated were your submission scores (public vs private). I was a bit surprised at the lack of correlation for my submissions.