Support via the XDA forum thread "General FYT based Spreadtrum uis7862 (unisoc ums512) - Q&A, Mods, tips"
The zips that can be found in these sub-folders can be directly unzipped to a clean, empty Fat32 formatted USB-stick or SD-card.
When this USB-stick or SD-card is inserted into your unit, the unit will recognize it as a flashable firmware.
Notes:
- These flashable firmware files will leave all your installed apps and settings as they are. Only the files/apks, when relevant, will be overwritten.
- Some scripts and mods are universal FYT mods for sc9853i, uis7862 (ums512) and for sc9863a (uis8581).