I downloaded KSE from this site. I've tried re-downloading twice to see if my internet was the issue, but sadly that is not the case.
Last night, I did try to see if a friend's laptop that I'm currently fixing for him and my college laptop would run it. Mate's laptop has 8.1 and ran it just fine and so did my college laptop. If nothing else, I could try editing my saves on that seeing as I have KOTOR 2 installed to play in my free time. I still would like to get it working on my desktop however.
And Yes, I am using the steam version.