Hi Steve, I've made my experiment simple, by playing with the DumbZPatterns examples, testing one rack under one specialist. Here is the skinscript: WITH Deliverables.getItem(self.id) COMPUTE name=name, dueDate=dueDate, description=description, todoIDs=todoIDs WITH SELF COMPUTE name=name, dueDate='1973/01/01', description='unknown achee', todoIDs=[] The virtual instance is loaded by accessing attribute of 'name'. I thought any calls for inexistent objects in Deliverables would turn out default values. Yet the test result turned out an not_found error. The following modification (change to 'otherwise' clause) didn't make a difference: WITH Deliverables.getItem(self.id) COMPUTE name=name, dueDate=dueDate, description=description, todoIDs=todoIDs OTHERWISE LET name='unknown', dueDate='1973/01/01', description='unknown achee', todoIDs=[] One more question, i.e. the following expression WITH Deliverables.getItem(self.id) COMPUTE name, dueDate, description, todoIDs also trigered the 'not_known' error for every objects in Deliverables. Where goes wrong? Dirksen __________________________________________________ Do You Yahoo!? Yahoo! Shopping - Thousands of Stores. Millions of Products. http://shopping.yahoo.com/