I now have 4.15 working with sound with Realtek audio in Windows 10!
After failing to get the game to start despite trying all 8 install options twice, I have been trying a few alternative fixes.
The thing that worked for me was selecting "Windows Sonic for Headphones" under "Spatial sound" in my Windows 10 speaker options. On my PC setup these speaker options are most easily accessed by right-click on the speaker icon on the taskbar.
Immediately after doing so I tested the Creative sound install that I had done earlier and it works, with or without headphones! Woohoo! I don't see myself doing much real-life work today!
