You can either edit the .script in a text editor, or use a 3rd-party sql client (which must support JDBC).
The HSQLDB project also includes a (very) basic client.
For configuration details and script syntax see hsql documentation @ http://hsqldb.org/web/hsqlDocsFrame.html.
Whichever method you choose, keep in mind that you must first stop the Tersus application if it is currently running, as Tersus loads the database in standalone (exclusive) mode (see docs above for details).
For best results, use the Firefox browser..