In order to have a "single blog and single gallery"-setup, I added the following to Scott's communityserver_override.config:
(If your gallery's appKey is different from "Gallery", you should change it.)
<Override xpath="/CommunityServer/Gallery" mode="new" name="defaultApplicationKey" value="Gallery" />
And this to siteurls_override.config:
<Override xpath="/SiteUrls/transformers/add[@key='##photogallerydirectory##']" mode="change" name="value" value="" />
<Override xpath="/SiteUrls/locations/location[@name='galleries']" mode="new" name="physicalPath" value="/photos/" />
<Override xpath="/SiteUrls/locations/location[@name='galleries']" mode="new" name="type" value="CommunityServer.Galleries.Components.SingleGalleryLocation, CommunityServer.Galleries" />
<Override xpath="/SiteUrls/navigation/link[@name='blog']" mode="remove" />
I think it's correct (it works), but I'm not completely sure 