If it’s just the silhouette node causing this, it is most likely the clip operation is not working anymore. I wasn’t actually testing that part of it just the parallax.
That should probably be rewritten a different way since it doesn’t really make since to rely on clipped UVs as an opacity mask. It should probably just check if offset is less than 0 or greater than 1 and return an opacity mask rather than clipped UVs.
Actually UE4 does have POM now, it has been checked into engine for a few weeks now and will be in the next public release. It doesn’t have the silhouette mapping though since I don’t think it makes sense to support since it’s such hard to use feature. The version in that material you posted only works for simple square 0-1 uv shapes it won’t work on any random floor shape you use. There is no easy way for it to work on arbitrary UV boundaries.