Prerequisite: You need Java since version 1.4. You can get the latest Java version from java.com.
Download either delta.zip or delta.tar.gz (these two archives have the same content except that delta.tar.gz contains Linux shell scripts instead of .bat files)
Extract the archive to a new folder (you can also extract a new version over an old one)
Run it by either using one of the start scripts or by double-clicking on delta.jar
Note: this package already contains some sample files, projects and XML-Language definitions. On the first start, it opens one of the sample projects (HTML-MHB).
Any problems, questions regarding DELT/A or request for new features? Mail me.