The binary version for MySQL Cluster 7.1.15a has now been made available at http://www.mysql.com/downloads/cluster/ (GPL version) or https://edelivery.oracle.com/ (commercial version)
A description of all of the changes (fixes) that have gone into MySQL Cluster 7.1.15a (compared to 7.1.15) can be found in the official MySQL Cluster documentation for Cluster 7.1.15a Change log.