Have that exact same problem. On the Free Flight screen, I can actually move the map around and I can see a blurred version of it shine through the window-like UI elements such as the Departures and Arrivals gizmo.
Outside of these elements, everything is black except for the airport markers.
Funny to see people complain about missing sounds. The SINGLE ONE time the sim managed to “finish” loading a free flight - as indicated by the bottom-right button - sound was the ONLY thing that was working, the screen was completely black.
Edit: Rolled back to the 566.03 driver. But I cannot test it, because it’s again impossible to even load the menu. The servers are spitting out occasional snippets of data at up to 80 KBit/s. (Yes, KILO-Bits.)
Edit 2: Managed to get to the Menu and Free Flight screen using the 566.03 driver. Still have the same exact problem.
Edit 3: SUCCESS !!! I’m now on the 566.14 STUDIO Driver (not the “Game Ready” one). For the first time, I’m seeing the background video during loading, and get to see the progress bar during all phases of loading, instead of only during loading of Sim Objects and World Data. The menu proudly shows our home planet, and the Free Flight screen has a working map in it!
I will try loading my very first flight now, with what appears to be a functioning renderer.