Hello people

I'm really a beginner but I like new adventures.
I have a HP Elitebook 8540w where I'm trying to use BT5 in persistent mode.

I followed the wiki using Unetbootin with a 8 Gb pendrive but the boot always goes on hold for a while and finishes with a busy box shell
I tried the same with the SD card reader with 16 Gb SD and it happens the same

The same USB Pen drive and SD in a older laptop are perfectly working !!!

I tried to boot from the DVD and it works perfectly but not in persistent mode and the boot is very slow.
If I boot from SD or from USB Pen drive with the Live DVD inserted, the boot hangs for a while and than continues from the DVD successfully..

I tried to install BT5 on the SD but I end with a Grub error out of disk because grub2 in not capable to recognise the SD mmcblk0 at boot.

here is a print of the partition on the SD:

Disk /dev/mmcblk0: 16.3 GB, 16288579584 bytes
255 heads, 63 sectors/track, 1980 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00078649

Device Boot Start End Blocks Id System
/dev/mmcblk0p1 * 1 1892 15191040 83 Linux
/dev/mmcblk0p2 1892 1981 712705 5 Extended
/dev/mmcblk0p5 1892 1981 712704 82 Linux swap / Solaris

At the end I only need to have a live persistent BT working but i cannot manage on this laptop.
I tried with BT3,BT4,BT4R2 and BT5 always with the same result
Other laptop or desktop are OK without troubles.

Is there anyone that can give me a suggestion ?