How to run Unity3D release for Ubuntu?

I downloaded the Unity3D latest build for Linux, (.deb and .sh) that can be downloaded from here http://forum.unity3d.com/threads/unity-on-linux-release-notes-and-known-issues.350256/

The .deb package showed an error, and I guess it is because it says that it is for amd64 architecture, and I am running Ubuntu on a x86_x64.

The .sh file extracted in my Downloads folder the folder unity-editor-5.1.0f3, and inside it two more folders named Editor and MonoDevelop. Now, when I try to run the Unity program under unity-editor-5.1.0f3/Editor/ nothing happens, and I don't know why. Also, I have tried to run the program from console to see if there's any error in the execution but i have not managed to do that yet.

With the extracted files from the .sh it also comes a .desktop file and it does not work either.

If any of you have already installed unity3d and it runs, please give me some advice with my problem. I am in Ubuntu 15.04