Speaking of containers i have similar problem, but in my case there are 3 objects in container.
Every one have different sets of behavior (1- physics, 2 rts, 3...) so altogether they make something like "enemy chasing player system" and i havent figure it out how to spawn them via "System -> create object".
Basicaly there's "main sprite" witch always have position set to "sprite detector" (with physix).
"Sprite detector" always follows "sprite follower" (with rts).
"Sprite follower" always moving to player position.
If i spawn "main sprite" usually nothing happening - just sits in his spawn position.
When i spawn "sprite follower" it start chasing player, but no more sprites have been spawned - same with "sprite detector" - just bouncing around if player hit it.
But when i spawn all three of them... well i can't describe that whats happening on the screen