Hi,
I have created my store using nopCommerce and noticed that the low stock report does not work when you have stock (products) with attributes.
For example in the demo you have a ladies adidas trainer that has stock that should be driven by shoe sizes.
If you alter the stock levels to = 0 for each shoe size the Low Stock report does not include the ladies adidas trainers.
Manage Stock is set to the 'Track Inventory For this Variant by Product Attributes'.