When is Kuailian actually installed on Mac? Take the dmg from the Mac card on the download page, then drag the icon into Applications. Later opens come from Launchpad or Applications — not from the disk image on the desktop.
Running from the dmg makes the app “vanish” when you eject the image. That is a path issue, not a broken package.
If macOS will not open it, use Privacy & Security
When you see Cannot Open, go to System Settings → Privacy & Security, scroll down, Open Anyway. Apple’s page: Change Privacy & Security settings.
Read the chip line in About This Mac
Apple menu → About This Mac. One Mac card on this site covers common machines; details in silicon vs Intel.
Missing menu-bar icon: menu bar. Need the dmg? Open Download.