Seems my bane right now are werebeasts. Forgot to switch off invaders, and one showed up, a dozen civilians piled on top of it and all got bitten. So i crashed the game and took it up from the last save again.
There's definitely some sort of aggressiveness from civilians now - non-war dogs assaulted a kangaroo (which didn't properly fight back) and kept bothering it when it fainted from exertion, so i sent in the military. The kill was made by a civilian stonecrafter who had apparently decided to follow her husband into battle. She walked right up to the animal and wrestled it to death.
Good news: water "boulders" may no longer break bones by themselves, but water cannons still appear to be effective. A horse foal just died. The first hit didn't mean much, it was just struck by the filled cart and thrown across half the map. But when it then lay there unconscious, it was pushed a dozen steps further by an incoming blob of water and the skidding on the floor pulped its head. I'll have to see if i can get a cannon to work on an invadeable map, but i fully expect decent performance. Perhaps i should pick a volcano and go full magma?
Another bridge test, this time with random garbage, confirmed my previous findings - bridges throw stuff around, but the direction is absolutely random. They aren't (and probably never were) a replacement for catapults or anything that's supposed to put a projectile in a specific target. A 6x2 bridge flung items up to eight levels vertically and sixteen tiles horizontally. This suggests a simple application in fortress defence: shrapnel landmines. Have a bridge in an open-ceiling spot where hostiles may congregate. Load it with preposterous amounts of garbage. When large enemy forces are nearby, raise the bridge. Enemies may be hit by falling junk. Stone blocks should make for decent bulk scrap, but of course you can also use pointier items like trap components.