Other links that are useful are
- Basic info and stock rom and tools for flashing new ROMs - http://www.slatedroid.com/topic/72057-lenovo-ideaphone-a820/ From here you can get access to the stock rom, flashing tools and scatterfile. See the link in post #2 labelled with "Contains Flashtool and drivers". To put the CWM recovery image on the phone, use the scatter file from the above thread, but make sure you use the CWM recovery tailred for the A820 in post #3 of http://forum.xda-developers.com/showthread.php?t=2264398.
- A preloader that works if you really bugger things up - http://forum.xda-developers.com/showpost.php?p=42026715&postcount=833.You need to hold down the vol-up button at the same time as the power button to put the phone in meta-mode if you've bricked your phone and need to replace the pre-loader.
- See here for more info http://forum.xda-developers.com/showthread.php?t=1943442