In the current version of xDM, the default value of a boolean attribute is NULL, which can be confusing at first and create some issues when working on your model.
If you need False as a default value, the best way to do so is to create an enricher for that attribute, with the following syntax :
Case when Entity.Attribute = 1 then 1 else 0 end
Matthieu DE PILLOT DE COLIGNY
How to change the default 'null' value of a boolean ?