I’m on 2.78c
I made a model and gave it a skeleton, assigned vertex groups to each bone and left the armature modifier set but not applied. Then if I make any new animations in the action editor, they all get imported to the engine without having to do anything else.
Occasionally I’ll have one animation that doesn’t make it out of blender, but If I just create a new animation and copy the key frames over then then it works.
I also noticed that you need to set the frame start and end time equal to the values of your longest animation. My longest animatino is a walk animation that’s 30 frames, so i have to have the end frame set to 30 at export time or it will be shortened when it makes it into JME.