There was a similar question here:
https://www.mobileread.com/forums/sh...d.php?t=351860
And there is some additional info here:
https://www.mobileread.com/forums/sh...d.php?t=341194
You only need the KFMon package; currently: OCP-KFMon-1.4.6-89-g8daae26.zip
You can find it when following the second link in your original post, then follow the instructions.
You don't need to download any other release package (e.g., from your other link). If you want to update KOReader you can always do it later over-the-air, once you got it running again.