Here is an Android 4.2.2 Jelly Bean rooted firmware for the PiPO M6 PRO (aka Max-M6pro) for both WiFI and 3G models. This custom firmware is based on latest PiPO official update version 1.1.6 dated 2014/03/18.

(M6pro新UI_1.1.6_update_20140318.zip / M6pro_software_Chinese_3G&WiFi_20140318)

Build information:

Kernel: Linux version 3.0.36+ (root@alex-System-Product-Name) (gcc version 4.6.x-google 20120106 (prerelease) (GCC) ) #227 SMP PREEMPT Tue Feb 25 14:30:59 CST 2014

Android 4.2.2 JB: rk30sdk/rk30sdk/rk30sdk:4.2.2/JDQ39/eng.root.20140318.191857:eng/opinions-on-teclast-p90hdst-keys

ro.rksdk.version=RK30_ANDROID4.2.2-SDK-v1.00.00

Custom firmware features:

• root with latest SuperSU version 1.94 (free version)
• removed most Chinese and unnecessary applications
• Google Play Store fixes so more application are visible/compatible
• updated busybox v1.21.0.git (2012-11-29)
• Unix like init.d boot scripts support, more details on init.d scripts here
• changed permissions on external sdcard to allow write access
• disabled OTA updates (may cause problems, see Notes below)
• increased space for applications (/data partition) to 7 GB
• kernel modules (cifs, tun, lan, serial, xpad) compiled by Oma & Crew RKTablets, thank guys!
• optional ClockworkMod (CWM) Recovery easy install package
• optional Deep Sleep fix for some Rockchip RK3188 based tablets ArcTools package (should not be necessary as Deep Sleep issue is expected to be fixed in this update)

Notes: 

- any update received thru OTA may interfere with our custom firmware, we recommend to refuse any update pushed OTA.

Download: kasty-pipo-m6_pro-422-116_20140318-rooted7.zip

Flash with Rockchip Batch Tool version 1.7, use Restore button.

I flashed this firmware and verified it is working on a PiPO M6 pro  (thanks sclstore.fr for their support with a test device) Unfortunately, I don't have much time for extensive tests on this new firmware release, users feedback is welcome.