Birt runs with the webtop (in fact it is a java application, viewer, which runs over a tomcat server) or it runs with a runtime.
The runtime could be installed without baan but needs java.
So using the webtop you will access directly to the viewer.
I noticed that printing from the worktop or the menuBrowzer, with the device RPT, the viewer is not displayed but a csv file is created in the temporary directory :
This the complete name of the file must then fill the parameter DS in the BIRT report to produce a document.
I use this method to test a report within the birtdesign studio or RCP.
It would be possible to add a script to a device RPT_BATCH, for example, which prints first the report using the device RPT and then call a shell to produce the final report using BIRT.
This shell is included with the runtime of BIRT.