@orokusaki, are you still experiencing difficulties? May I suggest upgrading to PostgreSQL 9.3 (freshly out!)? Some write that the new Streaming-Only Remastering capability turns aa replica in a set of replicas into the new master for all of the other replicas. Apparently, it's even more useful in combination with the cascading replication you are using in 9.2
In PostgreSQL 9.2, cascading replication really requires file-based WAL archiving to work in case of disaster recovery. PostgreSQL 9.3 will not require that: you can set up large replication clusters of whatever length you want without any WAL archiving.
See more here: https://wiki.postgresql.org/wiki/What%27s_new_in_PostgreSQL_9.3 and hereMore information: http://www.databasesoup.com/2013/01/cascading-replication-and-cycles.html