I was using a Live Lubuntu Trusty nightly, so the specifics instructions may vary, but here's what I did:
1. Boot from my USB stick
2. At the boot menu, highlight "Try Lubuntu without installing"
3. Press F6 to bring up the kernel command line
4. Add "live-media=/dev/xxx1" to the end of the line (but before the final double hypen).
In my case, the path I needed was /dev/sde1, but you will have to use the path to your install media.
I finally figured out a workaround.
I was able to boot into a live session by passing the "live-media=" parameter from the boot menu, specifying the device path of my USB device.
(See http:// manpages. ubuntu. com/manpages/ hardy/man7/ casper. 7.html for a description of the live-media parameter.)
I was using a Live Lubuntu Trusty nightly, so the specifics instructions may vary, but here's what I did: /dev/xxx1" to the end of the line (but before the final double hypen).
1. Boot from my USB stick
2. At the boot menu, highlight "Try Lubuntu without installing"
3. Press F6 to bring up the kernel command line
4. Add "live-media=
In my case, the path I needed was /dev/sde1, but you will have to use the path to your install media.