your issue is that you are using "local space position"
local space position moves the object relative to its own coordinate system, which is moving. It seems you want the object to move towards "destX/Y/Z", so what you should do is "point" the bullet at that location using "look at (parent/world)" and move by local space vector (0,0,speed) per tick
Another option if you don't wish to affect the rotation is to set the objects position per tick in a "parent/world" type set position action. You'll have to subtract the current bullet location in xyz from the current destination in xyz, then normalize those values by distance (divide them by the 3D distance) then multiply them by speed.
// get the difference vector
delX = bullet.destX-bullet.initialX
delY = bullet.destY-bullet.initialY
delZ = bullet.destZ-bullet.initialZ
// get the distance and normalization factor
dist = sqrt(delX^2+delY^2+delZ^2)
// normalization factor is multiplied by the speed,
// so basically the del vector becomes a (unit vector)*(speed) when multiplied by normalization
normalize = speed/dist
// move the object
set parent/world space position:
you can export animations with the blender exporter:
https://github.com/mrdoob/three.js/tree ... rs/blender
for now only morph animations are supported but as i've stated skeletal is very close.