With the recent update in Maximo 188.8.131.52, the BIRT engine has been upgraded. Here is the newest development guide or view the PDF. If you need the guide for Maximo version 184.108.40.206 to 220.127.116.11 you can go here or for Maximo version 7.1 you can go here.
Along with the new version of BIRT, there is an update utility that will help you automate the process of applying updates to report designs instead of individual reports. Keep in mind, this utility does not upgrade your BIRT 2.3.2 reports to the latest and greatest. You will have to do that manually.
You can will also want to have a look at this post from Jason Verly on Implementing a Maximo 18.104.22.168 BIRT fix in 7.1.1.x