Thank you for the report. Sorry you're having problems with the utility. I'm surprised that nothing is being installed after downloading. You might want to try uninstalling the utility, rebooting, and then do a clean install. I don't know if that will fix things or not. I'm not seeing that problem on any of the test machines.
If the Install button isn't working for you, I have a possible workaround. Since the utility has downloaded all your drivers, you might want to just go to the folder with the drivers and run each one individually. I know it's not a great solution, but at least you can get the latest drivers. The folder icon will open the download folder with the drivers so you can run each of them from that folder.