Hi!
I don't think I have the time to actually participate in this challenge, but here are a few of my observations/comments about what has been said in this thread.
1. Legend mode is toggled by an (e)xtended option in the design menu. It seems that it is bugged that if you hide it as important events remain visible even though they are not counted as revealed ???
The current default for the legend mode toggle is that ALL HISTORY IS REVEALED, so if you wish to have a hidden history, you do need to change the extended options, sorry.
2. Bug reports seem to indicate that culling historic persons does affect world creation (a behavior I personally consider buggy, but whatever). Therefore, besides the seeds, the culling state would probably be required.
For this kind of challenge, non-culling seems more interesting.
3. I have not done much playing in Adventure mode but have done a little bit of fortress building. Concerning engravings, I have witnessed that dwarves in fortress mode do engrave historic events, however this makes up only a small part of their repertoire (very often, they simply engrave things, then, they often engrave the insignia of their clan or their civilization, and only occasionally they will do historic events). I once witnessed a fascinating story enfold with two humans and 3 sasquatches spanning a bit more than 100 years ... and I still don't know WHY the dwarves chose these incidents.
I remember people commenting about site engravings here on the forums, so I think it is not unprobable to see such things. However, there has also been musing that site creation time limits the number of available motifs. A lot of settlements are founded in the year 1 when nothing has transpired yet, so this may also hamper the existance of such engravings.
Anyhow, I am planning to have an eye on this thread since the history and such stuff are really interesting, so I am curious about what people will experience.
Deathworks