As of now, starting Solr in standalone mode using './solr start' starts up Solr without any core. Trying to create a core from coreadmin UI doesn't work and errors out (when using defaults).
Error CREATEing SolrCore 'new_core': Unable to create core [new_core] Caused by: Can't find resource 'solrconfig.xml' in classpath or '/lucene-solr/solr/server/solr/new_core/conf'
The only way to get it to work would be to use the /server/<configset> directory to be the instance directory and then, the core creation would create unwanted directories in there. The only way to clean that up being,