Hi i have managed to set up a usb thumb drive to record to in the spare record folder. How do i test it to see if it works? or does it only kick in when the main recording folder is full.

Sorry. Spare not supported in modern Android because no access to real folders

what version of android do you call modern i have 8.1. I have also managed to set up a usb drive as the main recorder in the main recording section and it actually works.

Hm. Android 8.x is good for your case. Modern shield firmware use Android 10 and all problems with >= 10.
Are you sure about Android 8.1?

ps: Check write access in app properties in Android settings

Yes it's 8.1. I use a A95X Max 4K Android TV box Android 8.1 Oreo
2.5″ HDD/SSD Bay for Expandable Storage
4K UltraHD Video Output
4GB RAM / 64GB Storage
Dual-Band Wi-Fi w/ 1GB/s Ethernet Adapter RJ45 Port
The only thing i can see in the ProgTv app permissions is Storage, read the contents of the USB storage and modify or delete contents of
the USB storage, nothing about write access.