Drag a product from the Stardraw products list.
Connect both inputs and outputs to other devices.
Add an input stub and label by using 'unlock' feature and copying an existing one.
Group the product with the new input stub/label.
Go to 'Products' view in Dashboard.
Newly 'grouped' product is no longer shown used....
Ungroup and the device is magically shows "used".

Maybe it's just me.