derived means that it should not be stored because it can be recomputed from the information available in the model. Anything that is not declared as derived gets saved.
Doru
ok we wrote a test that shows that a model saved and reloaded as the same entities and properties than the one it originates from. Now since andre filters and keep only Number we may have problems.
We should check that because I would save everything that is not derived regardless of its type.
Stef