One of the super useful features on Linnworks Desktop is that you can click the + and see the stock levels including available level of every item on that purchase order. This lets you know whether any customers are waiting on a product in that purchase order. Linnworks.net doesn't have this functionality.

For example, see the screenshot. It's very easy to tell that I need to book in this PO because there are open orders waiting on it.

Adding 'stock level' and 'In Open Order' columns in the Purchase Order Edit screen would be even better.

Same as you see in the 'my inventory' screen 

I really like PO in .net but working on window where is only 5 lines is very difficult, and half of the bottom of the screen is blank for what? Anyway it is not only PO screen it is same issue on every single screen, lack of expand or resize.