Can you try my branch? https://github.com/0lento/UnrealEngi…PR-FleX-4.19.2. This branch used to build fine with VS2017 and has build fixes that are not present in the NvPhysX’s branch. I made a PR for the fixes but Nvidia ignored it this time around (they accepted some similar PR I sent earlier), I’m guessing relevant people are just not following the PR’s at all.
There’s also 4.21 port here: https://github.com/0lento/UnrealEngine/tree/4.21-FleX (credit to trashbyte for the 4.21 fixes).