xVarConfigAuthor is needed to create the configuration profile files for xVarConfig. These files with the file extension .xconf are containing the informations about available configuration options and their possible values, along with a description for each option and value.
xVarConfigAuthor is freeware. That means they it be used free of charge. Also it is not planned to ever change this
Note: whether you use the stable or beta version, once installed, xVarConfig will automatically update itself, always getting you the newest version.
Beta versions are not fully tested to be stable while on the other hand they might contain features or bug fixes the stable version doesn't have yet. Use this if you want to help testing or if you are interested in new feature/bug fixes.