Can't access Volume postproccesor with Application SpaceWarp

So i decided to use the application spacewarp on my project and then i wanted to add some Volume postprocessor effects, and modify them by code. But i can't no longer access the Volume script (yes, im using de "using UnityEngine.Rendering")
I figured out that the problem was application spacewarp modifying pipelines packages, because when i access the Volume script on the project it reference an external folder (outside my project) and this folder is one on the application space warp project that you have to download from git.
I read something about the assemblies, but im not very familiarizate with it.
Also i tried to use the Volume on another project without spacewarp and it worked, so it must be that.

Any ideas on how to get the reference to that Script on a external package?