There are two kinds of documentation regarding the Tallis/PROforma suite.
PROforma language documentation (guideline authoring)
This is documentation intended for people who want to understand PROforma language semantics, write guidelines using the Tallis authoring tools and optionally enact them on the web application. The documentation is written for versions 1.4, 1.5 and 1.6. It is located in our older site at archive.cossac.org/tallis/. Some useful links are:
Tallis documentation for software developers
This is java level documentation for software developers that want to embed tallis engine to their application. It consists of: