Hi saeromm,
I think the best thing to do here is to create an object parent, and create your static sprite batcher and gameobject as a child, as the alternatives would mean a lot more runtime complexity.
I'll explain the change which has made this break. In previous versions
SpriteBatcher
Sprite1
Sprite2
Sprite3
GameObject
Sprite4
etc. would work, as the gameObject would simply be left, but Sprite4 wouldn't be merged properly.
You can build complex hierarchies now, paving the way for a "Dynamic sprite batcher" in the future.
In the current version, this will work correctly. However, any components attached to GameObject would be lost, as it tries to remember the hierarchy, and will need to remember all other components too.
I suggest doing this if possible.
ParentGameObject
StaticSpriteBatcher
Sprite
Sprite
Sprite
GameObject (with collider)
If not it will be possible to make a mashup version which will work as it used to. Let me know if you'd like to do that and I can offer some advice on that.