To make it easy for my customer to choose his category to save an item, I decided to use Dynamic Cascade. I read this topic where Klass say : "if your purpose is to store only last level category then only that select should have standard-article-catid as storage (the same storage as it is in article category field), otherwise selcts will be overwritting each other."
If I let my 2nd field with storage Standard-Article-catid, the category is not saved in xx__content catid, but in a field created in xx__cck_form_myform and called catid.
What I have done is modify the storage to Standard-Free-catid with parameter on xx_content.
Is there any reason for that or did I miss something ?
BTW, it works now and items are correctly saved...