Hello :), if you search the last stable version i found it !!!.
Link : http://www.mediafire.com/download/zo4vcng4ghh2oo1/miui_HMNote2_V6.7.10.0.LHMCNCH_f75442bc6d_5.0.zip
Source : http://en.miui.com/thread-166939-1-1.html
Sorry sorry i found it the "V6.7.10.0" :).
Link : http://www.mediafire.com/download/zo4vcng4ghh2oo1/miui_HMNote2_V6.7.10.0.LHMCNCH_f75442bc6d_5.0.zip
Source : http://en.miui.com/thread-166939-1-1.html
Hello, i uploaded the stable rom "V6.7.5.0" on mega. It's better to let a stable version for your mum :).
Link : https://mega.nz/#!1gACgS6J!sa1Iq0axrQdk1Wz4RWwJxK9O3e4mdTHphMhh0woSYxo