It appears that there are still a number of users who keep persisting with trying to get the Sky Go app to work on their desktop's without success!
I have tried repeatedly to install the "official" desktop app on my own Windows 10 computer and despite deleting everything and clean installs I also cannot get it to work properly.
What I have done is accept that Sky are not treating customer concerns properly, and installed an emulator instead.
I can only say since I installed the emulator I have had faultless watching of Sky Go without any of the usuall buffering and stuttering I experienced before with the Windows App and the previous silverlight browser version.
If it helps, I installed Bluestacks Version 3N Client Version 4.1.21.2018 Engine Version 4.3.28.4020 from www.bluestacks.com
I then installed Sky Go app for Android from Goole Store, ensured I added the emulator to the managed devices on my Sky account and adjusted the emulator settings to maximise the memory and core's and pixel account and hey presto it works.
For some reason this is far superior to the previous experiences with Sky Go when I used it within the web browser and silverlight!
Thankfully, since using this method I have managed to watch the Test Match and Rugby Leauge without issue, "happy days"
If you are tired of trying to install Sky Go on your desktop give this a try, if it does not work it can easily be uninstalled, what have you to loose?