Joshua Ashton released a small tidying up version of D9VK yesterday, fixing a few issues to give you a better experience with this D3D9 to Vulkan layer.
It adds in support for SetSoftwareVertexProcessing and GetSoftwareVertexProcessing with the rest of D9VK 0.22 amounting to fixes for reported issues.
One such issue was found with The Sims 2, as it would "try to render shadows to a A8 texture and completely mess everything up" so that should now be solved. A regression was put to rest where "full constant uploads were happening all the time", some games moaned that drivers were too old which was solved and it will now return "D3DERR_INVALIDCALL when trying to create textures with unsupported formats".
See the release notes on GitHub.
If you've been testing D9VK directly with Wine or in Steam Play, do let us know in the comments what your experience has been.