It is up to the artist as to what software and render engines they make their products compatible for.  Renderosity has no control over this.  If you have a problem with DAZ-only content for Gen4 or props, then take it up with the vendor.

Also, it is best to get used to this-- V4 is gradually going by the wayside in favor of Poser-ver.-Dawn and Genesis 2 female/male.

 

In regards to props however, you can always ask the vendor to release some Poser shaders or whatever for them.  I know that Dariofish will do this for his products-- usually for free.  Shaders and lighting is an entirely different matter, and it depends on whether or not the vendor knows how to make them for both systems.