BTW be careful that demo product data in v6 is (at least partially) set to "Consumable" type at the moment, not "Stockable", which will never trigger a stock level error and will quietly go to negative (that's the whole point of Consumable products for which you don't track stock level precisely or at all)
BTW be careful that demo product data in v6 is (at least partially) set to "Consumable" type at the moment, not "Stockable", which will never trigger a stock level error and will quietly go to negative (that's the whole point of Consumable products for which you don't track stock level precisely or at all)