This project is best with the master revision (it anyway pulls latest data from the repository). However, the scripts (mainly configure-get.sh) are rather stable and hence a release is (over-)due. Users are encouraged to rely on the master revision of XCONFIGURE.
The online-documentation is directly readable at GitHub, but also available in a reformatted form at ReadtheDocs including the capability to search the documentation. In addition, an offline document is available as well (PDF).