If I change tab on the admin panel for ContentReference property, his value is missing.
This is cms bug?
For example Image in the ContactPage in the AlloyMvc.
Could you try to give a bit better explanation/reproduction steps for this? It's very hard to understand what you consider a problem with the explanation above.
Set value for property with name "Image"(property type is ContentReference)
In admin panel change property tab
Property value is missing