*Appears out of the woodwork* Woohoo! New update!!
One small thing(and I just did a quick test of it to make sure it hadn't changed). As for the bonemeal reaction, there is a long-outstanding bug in DF that custom reactions involving bones do not honor stack size. IE, I just slaughtered two bighorners, two dogs, and two cats, and got a whopping three bonemeal out of it, despite there being 10-28 units of bone in each stack. There is a workaround to this, but it does add a central step that increases the need of ponypower. The reaction of making bone ammunition honors stack size, and ammo can be used as a reagent in reactions. It's pretty simple to change the reaction for bonemeal itself to require 10 units of bone ammunition, instead of the bones themselves.
I fudged this reaction into working for Valikdu's mod about six months ago(I meant it when I said it's a long-outstanding bug, it wasn't new then, either) for bone construction materials from information
here.
The modified reaction would simply change:
[REACTION:BONE_GRINDING]
[NAME:grind (2) bones to bonemeal (flux)]
[BUILDING:GRINDER:CUSTOM_B]
[REAGENT:A:2:NONE:NONE:NONE:NONE][USE_BODY_COMPONENT][ANY_BONE_MATERIAL]
[PRODUCT:100:1:BOULDER:NONE:INORGANIC:BONEMEAL]
[SKILL:MASONRY]to
[REACTION:BONE_GRINDING]
[NAME:grind (10) bone ammunition to bonemeal (flux)]
[BUILDING:GRINDER:CUSTOM_B]
[REAGENT:A:10:AMMO:ITEM_AMMO_BOLTS:NONE:NONE][USE_BODY_COMPONENT][ANY_BONE_MATERIAL]
[PRODUCT:100:1:BOULDER:NONE:INORGANIC:BONEMEAL]
[SKILL:MASONRY]This will make it so the reaction uses two bones, as intended, instead of two stacks of bones due to the bug. If you wanted to make it take more bones, simply take the number of bones you'd want it to use and multiply by 5.
For those who use bone pellets for training, it might get annoyingly micromanage-y but I'm unaware of any other work around, and careful stockpile use should be able to fix that. Set ammo stockpile to only accept lower quality ammo, and have a dedicated grinder take from there to grind bonemeal, and leave the higher quality stuff to be used by ponies for use, or some such similar thing.
Also, if I remember correctly, it doesn't require a world regen after changing the reaction in the raws.
Anyway, if I find anything else not working as intended in there, I'll be sure to pop in with what I find. I'm usually a pretty quiet tester until I find something I can identify the root problem of, so unless something big and obvious breaks, I probably won't be the most help there.