Where you cant download? And what you trying to download.
Here is the simplest solution.
Open this url
https://github.com/kasymovga/qrexuizlauncher/releases/tag/2020.05.25
choose you OS, lets say its windows.
Click to RexuizLauncher.Windows.exe
Your browser have to start downloading it.
Move file to your desktop for example. And run it. It will start and download all other game files. The game will start after download is complete. Next time just click to RexuizLauncher.Windows.exe again and game will check for update and start after.