There are a few TPC-R tables with over 1 million rows. So a subset of the data should exported as CSV. The CSV files for each table can be loaded via a MySQL script to load the data.
The DDL file can be created from the model created from the JDBC import by exporting it as MySQL DDL.
If needed, here is a link with instructions on how to add a SQL Server data source:
http://mpashworth.wordpress.com/2012/01/26/configuring-a-sql-server-data-source-within-jboss-7-1/