Usual answer to "won't install" issues. Try turning off your anti-virus temporarily. Its possible that its seeing a string in the download as suspicious and blocking it. The usual indicator is that it stops the download after it has begun and always at the same point. Also check your firewall, could be it doing the exact same thing.
Does it always seem like its at about the same point? Everything has a reason, whats the reason that the launcher stopped? Did it go on a lunch break? No. Something caused it to stop, or for your computer to think that the launcher stopped. Maybe your computer stopped the launcher.
Computer at work didn't, so its probably local to that particular computer. First things to investigate are the obvious.