I've never bricked a CAS4. I assume it will be similar to what happens on CAS3 downgrades; If I had to take a guess ; the flash is probably the issue. EEPROM is likely intact if the key data is all there.   Before all of the repair utilities on CAS3, you would load the flash from another similar vehicle. This would bring it back to life, to be flashed with the proper file. I know BIM tool will update the Flash ; I am SPIT BALLING here so don't take it as gospel. I would load the flash from another car, see if the vehicle is responsive at that point (make back ups!!)   Once it responds, I would get a key programmed to get the ignition switching on. Then run the Flash update via BIMtool

Here I am again rambling. All I had to do was make an extra key. Well I turned this job into an poop show. ABRITES would not write key to vehicle holding key to antenna, I did test it first. So, I broke out IM608 which quickly failed and would not restore data.  Now vehicle will not power on and key data does not read.  My question is what part of data is bad? The flash reads ok and I took the CAS out and ACDP reads key data out of it. Is it just coding that messed up? I am trying to fix without writing all new data. Just hoping someone has insight . 

The steering lock is also involved.

I don't know how I missed this, but I am offering a belated thanks for all your effort.

Understood.  I thought in the video that your remote did not function after programming and was wondering if there was a problem with this car or was there some hiccup that needed to be straightened out.  Thanks for making the videos, you do a great job.