@Robs_Shed_of_Tech Thank you for the video, quite impressive are the possibilities of the FP4 
I already used an external monitor (TV & computer screen) for my FP4, either wireless (Miracast) or with USB-C docking station (with DisplayLink Presenter), but I was not aware of the “Desktop mode” option in Developer Settings 
However I got lost in your explanation for the laptop part:
- Is it a regular laptop? So can I use any laptop with USB-C port for this?
- How do you configure the laptop so it knows that he have to take the USB-C signal as an input instead of output?
- When you connect your two devices (FP4 and laptop) directly with USB-C, is your laptop already on (running Windows) or turned off? If I plug out the USB-C cable, do I go back to Windows?