I will reply myself after lot of experiment
As I did not know what have happened with my droid - second hand buy - I got it already with 4.1.2 Verizon stock and at the begining I was doing a lot of experiments with flashing, I decided go back . I took the rom VRZ_T894_6.5.1-16~219_1FF_01.xml.zip and tried to flash it using RSD Lite for linux - it required the linux-mfastboot which support some multi-part flashing - otherwise it was limited to 1GB . Even if the flashing failed for some partitions (probably bad enciphering key used) It flashed the webtop content and preloaded OK. Than I could reflash the VRZ_XT894_9.8.2O-72_VZW-18-8_1FF.xml.zip
which worked OK even for system and directory structures (but apparently it does not touch the webtop )
So I have had correct partitions installed stock rom and used motofail to root it, installed safestrap 3.75 with modified partitions and finally I have had it exactly as described above.
Re: xt894 and xt912: Safestrap 3.75 for the unused partitions...
I will reply myself after lot of experiment
As I did not know what have happened with my droid - second hand buy - I got it already with 4.1.2 Verizon stock and at the begining I was doing a lot of experiments with flashing, I decided go back . I took the rom VRZ_T894_6.5.1-16~219_1FF_01.xml.zip and tried to flash it using RSD Lite for linux - it required the linux-mfastboot which support some multi-part flashing - otherwise it was limited to 1GB . Even if the flashing failed for some partitions (probably bad enciphering key used) It flashed the webtop content and preloaded OK. Than I could reflash the VRZ_XT894_9.8.2O-72_VZW-18-8_1FF.xml.zip
which worked OK even for system and directory structures (but apparently it does not touch the webtop )
So I have had correct partitions installed stock rom and used motofail to root it, installed safestrap 3.75 with modified partitions and finally I have had it exactly as described above.