Blocked by your OS? That's expected.
These builds are not code-signed yet, so macOS Gatekeeper, Windows SmartScreen and some browsers flag them as coming from an unidentified developer. The binary is the Electron shell in this repo — nothing else. Here's how to allow it:
BrowserIf the download is stopped, open your downloads list and choose Keep / Keep anyway.
macOSRun xattr -cr X17z-darwin-x64/X17z.app, or right-click the app → Open → Open. If it still refuses: System Settings → Privacy & Security → Open Anyway.
WindowsSmartScreen → More info → Run anyway. You can also right-click the .exe → Properties → Unblock.
LinuxMark it executable: chmod +x X17z-linux-x64/X17z.