Not able to install using the latest Live CD

Binary package hint: ubiquity

I downloaded the latest ISO of Natty using Testdrive last night (April 20, 2011). I made a live USB using the startup disk creator in Maverick.

I was hoping to be able to upgrade from 10.10 to 11.04 using this Live USB as per this article: http://www.webupd8.org/2011/04/how-to-upgrade-to-ubuntu-1104-natty.html . But no such option was offered on starting the installer from the Live USB.

The first screen was "Preparing to install Ubuntu", where it confirmed about disk space. And the next screen was the "Where are you" to select the timezone, after that the keyboard layout and so on.

The partition dialog box didn't appear at all, instead it directly started the "Install" window with the slideshow running, but nothing was being installed.

I eventually had to close that window, it said that the installation hasn't finished yet, I forcibly quit it and after that a message box came up saying that installation is finished and I may restart.

I will attach the screenshots and logs in the comments.

Thanks.

ProblemType: Bug
DistroRelease: Ubuntu 11.04
Package: ubiquity 2.6.6
ProcVersionSignature: Ubuntu 2.6.38-8.42-generic 2.6.38.2
Uname: Linux 2.6.38-8-generic i686
Architecture: i386
Date: Thu Apr 21 12:30:20 2011
LiveMediaBuild: Ubuntu 11.04 "Natty Narwhal" - Beta i386 (20110420)
ProcEnviron:
 LANGUAGE=en_US:en
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: ubiquity
UpgradeStatus: No upgrade log present (probably fresh install)