I've installed Activiz 5.8.0 on my project (I installed both 32 and 64 bits versions through the Nuget package manager).
I can import to the toolbox only the 32 bits RenderWindowControl component of Kitware.VTK.dll, when I try the 64 bits version it doesn't work (I can't even import it to the toolbox).
I'm using VS2012 64 bits edition.
Thank you for your help!