I don't use windows 8 very much so i can't speak from experience on it, but have you tried the usual things such as redownloading and retrying the install? Also make sure you have nothing running in the background (processes tab in the task manager works wonders for this, but dont touch the program if you dont know what it is) as stated by the error.
As for your question about setup steps, there really are none. The installer seems to be trolling you there, it installs itself by itself.