How do I add background in a new layer

I am trying to add an image as background to represent "sky".I created a background layer and i added the sprite in that layer.However the moment i added that sprint stuffs in my main layer start disappearing(i.e bullet not showing, enemy not showing etc....What i am doing wrong ?

Buggy one ->https://www.dropbox.com/s/tgdv41k9dclqxfx/workingdemolatest-bgfix.capx?dl=0

Working one -> dropbox.com/s/bt9k1d5hab7auht/workingdemolatest.capx

Everything you spawn is also on layer 0 with the background, and behind it in the z-order. Z-order shouldn't matter though, you should really be spawning objects on layer 1 or above, in front of the background. The objects you can see are not spawned and are already on layer 1 so they are visible in front of the background. Check your spawning events where it says layer 0 by default, you can update this to 1 or above.

The default layer 0 always has "Transparent" set to No. By moving a layer under it, you won't see it, unless you fix the values. Set Transparent to Yes on layer 1 and No on layer 0.

Also, it's best to spawn by layer Name, rather than number.

Thanks to both of you i have been able to add the background successfully but there is still an issue with the barrel...earlier the barrel will appear in front of monkey but now its appears behind it.I have already make sure that both are on Main layer and both monkey and barrel are at top of layer

Please have a look --> dropbox.com/s/fjey6g3m0pzi344/workingdemolatest-improved.capx

Thanks a ton for your help thus far

Event 13 you're still spawning on layer 0.

Ahh missed that....Thanks a lot plinkie