Update has just been posted:
http://dffd.bay12games.com/file.php?id=6378Fixed some of the bugs causing worldgen crashes and the errorlog comes up clean on a df install with no other mods. The summon extradimensional beings reaction will now produce a "soul essence" a dwarf can eat and then summon a critter, but like it says on the tin, extremely dangerous. You could summon a terrible demonic entity that kills everyone it sees. Or a spider-llama, for silky-goodness.
There are also changes you will want to make to vanilla DF to make it less crash prone if you're copying in the reactions and buildings manually: in entity_default.txt, under ENTITY:MOUNTAIN, under the values section, change [VALUE:LEISURE_TIME:15] and [VALUE:MERRIMENT:15] both to [...:-5]. Then copy and paste both of those in ENTITY:PLAINS underneath where it says [VARIABLE_VALUE:ALL:-30:30], so it should then read;
[VARIABLE_VALUE:ALL:-30:30]
[VALUE:MERRIMENT:-5]
[VALUE:LEISURE_TIME:-5]
This should stop more of the worldgen crashes.
If you follow the "copy the entire entity_default.txt provided in the "Vanilla Entity and extra info" folder into the raw/objects folder" then you don't have to worry about that, because I changed the value tokens in that copy of the file to already.
I've been experiencing only very rare crashes now with that included, and can almost always generate worlds in excess of 200 years. But there's apparently still something causing crashes, and I don't know if its vanilla DF related or mod related, and It happens too rarely to just start cutting out chunks of the mod and waiting to see if the crashing stops, because it's like a 1 in 10 chance of happening anyway, so I can generate 20 worlds in a row without problems and suddenly it crashes again.
@Angel; I did look into the masterwork versions of the file and I'll take note of them for later when masterwork updates. Thanks for sharing them!