Before you can install a custom HOSTS file in Win8, you will need to make a change in Windows Defender ... otherwise Defender will automatically remove your custom file and replace it with the default from Microsoft.
Hosts file is detected as malware in Windows Defender (Win8)
"This issue occurs because Windows Defender may determine incorrectly that the Hosts file was changed by malware"
The people that write the code detection for Defender are just lazy or don't get it! ... There has never been a malware infection that only affected the HOSTS file ... so why if nothing else is detected does Defender still determine that you are infected? So in order to avoid the false detection, follow the instructions in the above Microsoft article. Basically you will need to exclude the Hosts file from scanning in Windows Defender. Once you have done this it should no longer be an issue to install ... you can use the same instructions as Windows 7
Speaking of Windows 8 ... I ran the Win8 Compatability checker and although my machine meets or exceeds all the hardware requirements the report spits out the following: "PC doesn't support PAE, NX, and SSE2" What that boils down to is that I'll need to replace the motherboard and CPU ... that sucks! So I'm not sure when I'll be able to afford to rebuild my box as funds for this are really tight.
If you find the MVPS HOSTS file useful ... please consider a donation ... 
Folks I'm in the process of updating the HOSTS file now and it should be out in a few days ...