I don't want to mingle in any backstory, but all that needs to be known is that I have a computer with Ubuntu on it and I am trying to install Windows 8 from an ISO.

I am using the guide that can be found here which is a little more than four years old. Now, I've been able to accomplish everything up to Step 2, at which point I am stuck. I have downloaded the file found on that page, which can be found here, and have attempted to use it, as directed, quote;

"right click the downloaded Unetbootin file, select Properties and on the "Permissions" tab, check the "Allow executing file as program" box. Then simply double click it and it should open."

But, after having set checked the specified box and double clicking the file, nothing happens. Nothing is launched and nothing changes. I've been stuck here for several hours now, having failed to find a solution via Google.