while installing official cyan update on lumia 920 from wp black phonegets hanged/ restarts ,

[WPCentral Question]

morning today i got wp8.1 cyan update on my lumia 920 . in two parts .. first one was small it got installed very fast second one took one to two hour to download . then when i said install it now, at around 12pm it started , first gears came , i had left phone on desk , then i checked after some time screen was turning black then nokia name was coming and same thing is repeating till now , 5.15 pm ?? is it restarting ?? whats problem ?? i didnt even took backup ... two times even battery showed red .. at time of downloading and installation it was full .. i never had developers preview .. whats problem ?? more than 5 hours has passed if we skip downloding part ..

 

[chnas]

I have the same problem, I started cyan update 3 hours before but it's still on "working" screen. what coud I do to cancel or complete the update installation