One of my servers crashed due to a broken harddisk, therefore you have to live with a very reduced version of OpenStreetBrowser - there are no categories right now. You may still enjoy the background rendering ;) I'm currently in the process of building a new base for the OpenStreetBrowser: Categories written in MapCSS, using Overpass API as database and pgmapcss for processing. Also for displaying, the new OpenLayers ol3 will be used. The rewrite is already quite advanced, but still I need another month or two until the version can go online. Stay tuned!