[Motorola Droid RAZR] whirleyes:
For those who can't wait to run Motoblur JB rom. Now we have this two situation to run JB ROM :

A. Stick with ICS kernel

- Replace JB graphic driver with ICS.

Advantage :

- Can still multi boot ICS ROM.

Disadvantage :

- Camera, HDMI, webtop fc

B. Upgrade to JB kernel manually

Advantage :

- Without upgrading via official OTA, we can go back to ICS

Disadvantage :

- Need to patch all ICS based ROM with JB graphic driver. Maybe introduce new fc problem in ICS ROM.

- Must erase CID & boot by bp-tools

# BMM user can skip this. Erased CID bootmode is auto detect.

Option A: Run JB ROM with ICS kernel

This just a patch of graphics library needed to boot MotoBlur JB on ICS kernel.

- Requires ICS kernel.

- No customization is included.

- I only test on BMM 0.3.x recovery, but I think it should work on SS3 too.

What doesn't not work

- Camera

- HDMI

How to run MotoBlur JB on ICS kernel

Download this JB backup (http://d-h.st/uqA) Credit to artur & yoyurik

Go to your recovery backup folder. extract downloaded backup file

Restore system backup (For BMM choose selective restore, restore system)

Choose install zip package & install graphic library patch (Blur_Version.98.72.8.ICS_patch.zip)

Wipe Data & Cache

For BMM user.

- Don't turn off 2nd-init in boot setting.

Option B: Run JB ROM with JB kernel

This method requires you to erase CID partition in order to bypass region check.

Don't upgrade cdt.bin else you'll stuck with it & can't downgrade. This is safest method to play JB & go back to ICS

How to erase CID & flash JB kernel

Backup your CID. [IMPORTANT]

dd if=/dev/block/mmcblk1p18 of=/sdcard/cid.img

Copy your CID to safe place. Every device have its own unique CID partition.

Restore a clean JB backup (without my ICS graphic patch)

Erase CID & flash JB boot.img

fastboot flash mbm allow-mbmloader-flashing-mbm.bin
fastboot reboot-bootloader
fastboot erase cid
fastboot flash boot boot_jb.img

#Now the opposite thing, ICS graphics driver won't work. For ICS based ROM, only black screen on boot. Maybe patch JB graphic driver back to ICS ROM??

#If you don't use BMM, you have to boot your phone with bp-tools option

#Don't panic. As long as you didn't upgrade CDT & have a CID backup, you have a good chance to restore your phone back to stock.

How to restore CID & restore ICS kernel

flash ICS kernel

fastboot flash boot my_region_ics_kernel.img

Restore your CID backup.

dd if=/sdcard/cid.img of=/dev/block/mmcblk1p18

Misc info

Lesson learned

Lastly, It seems JB kernel is a little bit secure. So far not ROOT method available.

Make sure you have a backup root & CID partition before upgrading to OFFICIAL JB OTA.

Yes, backup CID before you lose root. Root maybe still possible by temp downgrade to ICS kernel from other region.

Kernel flashing fact!

I run few check from my kernel collection.

flashing kernel secure version >= secure version specified in cdt.bin, won't trigger error.

Lower version always trigger: Preflash validation failure

I got this hint from this thread. (JB Dual Boot - XT912) Credit to xlightwaverx.

For GSM user.

- Maybe you need to remove some Verizon APP so that you can passed setup screen.

- No GSM patch included. Maybe try to change some build.prop property to get data work.

If you can't understand above instruction, don't worry.

Sure someone will make a custom rom for you after this.

Disclaimer:

- I'm not responsible of what you do to your device.

Have fun & Happy new year.