The default configuration in the jbpm-jpdl-3.2.5SP5 package defines the path to the GPD deployer servlet as /app/upload in /deploy/server/default/deploy/jbpm/jsf-console.war/WEB-INF/web.xml:

<servlet-mapping>
<servlet-name>GDP Deployer Servlet</servlet-name>
<url-pattern>/app/upload/*</url-pattern>
</servlet-mapping>

This doesn't match with the defaults in the GPD/JBDS, and should thus be changed to <url-pattern>/upload/*</url-pattern>.