"the blocked/not blocked status", "the contact group in which the contact is located" are all pure Messenger settings and depend on you contactlist and your contacts' status, there is nothing about it to be saved. It is the protocol that is handling these... So impossible...
"the name given to the contact (when using the personalized names)", and "the alerts settings defined for this contact" are all stored with the import/export wizard IIRC.
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