I'm looking at the Fuses tab again and I suspect this is one of the very last parts of the app that the previous author worked on. Looking at the interface and the code behind the scenes, I don't think it was actually fully finished.
For now, I think I will remove the Components and Inventory tabs from Fuses. I don't think these ever worked at all so I don't believe anyone will have any data in these sections. If you have an objection to this, please let me know :)
My goal is to get the basic Fuses tab working 100% reliably, and per vehicle. We can work on refinements and new features in future versions.