Q:

using existing SLD style with postgis layers in Opengeo Composer

I have exported some styles from QGIS as SLD files and then loaded them into GeoServer.  I have published a couple of layers from a PostGIS database and these load nicely in the OpenGeo Composer with a simple YSLD style.
I now want to apply the more complete style that I built in QGIS so I went back to Geoserver and found 'available style' under the 'publish' tab of the layer.  I added the style that I had imported to the 'available' list but composer appears to ignore it.
It seems that the only way I can fiddle with the style is to edit the yaml.  I did try an XML to YAML converter and was unsurprised when the results were not usable.
I really want to have one definitive source for my styles. I don't mind exporting them from QGIS as files but I really don't want to have to recreate them in YAML by hand.
What am I missing?  

A:

GeoServer allows you to associate as many styles as you want to a layer. But only one of them can be the default style, that is the one that is applied to the layer if your client doesn't specify which style it would like. 
In your case, by adding the style into the available list you just associate the style with the layer. It sounds as if the composer will only handle the default style, so you need to go back and change that in the "publish" tab look for the default style box above the available list.

