Thank you for including Replication Markets! A couple of notes:
*We got to test that a bit in Round 8 when we discovered a coordinated "attack" that accounted for ~1/3 of our surveys. Some forecasts would have changed, prizes would have been won, but neither so much as we feared.
Interesting! We designed "safe mode" to be safe against the common newbie failure of losing all cash in a few big trades. It achieved that much at least. Each trade spent max of about *1%* of your cash, and moved it at most halfway towards your goal. A dedicated newbie could still burn cash, but it took effort.
Still, from your report, that may have happened more than I thought. If so, it may not even have achieved its main design goal. :-(
"The worst thing" was indeed atrocious. We fixed that fairly quickly, but ... ugh.
Thanks for the thoughtful critique. We're about to reuse the engine. I'm giving this some thought.