Samsung Galaxy S2 i9100 keeps getting Status 7 when installing CyanogenMod
Here is a FIX I found for you. Read thoroughly. This will solve your problem. 

The first mistake that most people make is flashing incorrect/old/outdated version of recovery.

The second mistake is not matching the correct/proper ROM/firmware to the device hardware.

Incompatibilities when flashing account for the majority of failed installations.

Always make backups/nandroids