I am having the same problem. I downloaded BT5-32-KDE and performed the unetbootin load to USB drive. It appeared to get through the installation without issue. But it
won't BOOT from it, I get a black screen with BOOT ERROR and nothing else.
I tried booting from the LIVE CD and the laptop doesn't boot, skips through to the harddrive to load windows.
I am new to trying to load Backtrack5. I am a proficient computer user though.