Dell latitude E5520 error during pre-installation ... Please help , sir.

[linw]

I'm having the exact same problem. Halting after DSMOS and Bluetooth.
I tried both unifail and myHack and added the bootpack from EDP page.

EDIT: This pack seems to solve it.
https://osxlatitude.com/index.php?/topic/2559-e5520-bootpack-problems-with-intel-hd-3000-hd-1920x1080/?p=19467