The files with the xcfg extension are configuration files for the Epeios software. They are in XML format, with namespace http://zeusw.org/epeios/xcfg (xmlns=”http://zeusw.org/epeios/xcfg”).
This files, at least the main file (the one which affix is the name of the corresponding software), have currently to be in the same directory as the corresponding binary.
Each software has is own set of recognized tags, but all have the root tag Configurations, enclosing a Configuration tag with a target attribute which value is the name of the software.
You can also use the xpp directives (which must currently belongs to xpp namespace).