So I was playing last night and my game crashed and besides it happening during world generation when I mucked with the advanced settings this hasn't happened before.
I am using LNP r55, and my game crashed twice in a Joyous Wilds region when some for of birdmen showed up in the area. The first time I believe it happened exactly when I tried to move up a Z-level and the other time it did so when a Kea man stole something from me.
Things that were different about this particular game are:
1-Trying to create a long running fort where everything but the inital seven dwarves is produced in fort. So I used fix/population-cap force.
2-In order not to get sieges based on created wealth that could easily outnumber my population I set the various triggers in that regard to 0 so that I would be sieged only once my population was at a certain level.
3-While I am using LNP r55, I may have genned the world on LNP r54.
I did search the bug tracker for any mention of kea's, but not birdmen in general (didn't occur to me at the time but will do so in a bit), but neither sounded as though it was relevant here. So any help in figuring out what could be the primary cause of this would be helpful.
Edit: It also occurred to me that I changed from seasonal saves to yearly ones, and while I thought nothing of it at the time but when I went to look for bug reports in relation to bird men I saw one about 2GB memory limit causing crashes and I suspect, but am not positive, that saving the game is an opportunity to offload and free up memory.