The "New" update wasn't a patch. It was a key. And Elias had just unlocked the door.
Ensure your GPU drivers are updated to the latest version for DX12 support. forza horizon 4 ultimate edition v13329042r new
If you have downloaded the release (usually distributed in six compressed archives), follow this step-by-step guide to avoid the common "stuck on splash screen" error. The "New" update wasn't a patch