I want to make an USB Stick, that can boot live-isos with grub2.

I've read a lot of posts about how to make it work for BT5 and now I'm stuck at this point.

I downloaded the backtrack5 gnome 32 and changed to initrd.gz with a patched one, to get the iso bootable (like discribed here http://this.is.thoughtcrime.org.nz/m...usb-with-grub2)

Now, BT5 boot screen is coming up and there are no errors, but it freezes at a certain point:
[3.768444] usb 2-1.2 new high speed USB device using ehci_hcd and address 3
after that it doesn't go on, cursor blinks, and you can type in anything.

Anyone an idea, what could be the problem?
What information do you need?

My Laptop is an acer Aspire 5750G:
Intel Core i5-2450M 2.50 GHz, 8 GB DDR3-1066, 640 GB SATA, DVD-RAM/R/RW, 39.624 cm (15.6 Zoll ) WXGA LED, NVIDIA GeForce GT 630M, 802.11b/g/n WLAN, Ethernet, webcam+mic, HDMI, VGA, 3xUSB

Thank you!