It works perfectly fine for me, and I didn't have to download anything else to get it. Can you describe to me exactly what is happening at each step in the following process?
1) Click this link:
https://mega.nz/#!3BYhBDqR!h2qdgOGpv9SEt7wMlAIPqOujvaXn5IF_Y6NyotfTv5k
2) Click "Download Through Your Browser"
3) Drag the file into your Applications Folder.
4) Manually Open the App
5) Click "Always Allow"
Be patient. The first time it opens it takes awhile. Let me know what happens!