I tried to upgrade my system from Red Hat Linux v6.1 to Red Hat Linux v6.2.
After a custom-upgrade, the installer checks for free space; at this stage
it reported back that xx MBs was needed, and the froze. Back didn't work, nor
did help or any other function in the (graphical) installer.
Notice that the system didn't freeze, I had full access to the virtual consoles.
The solution was to free up space on the HD and rerun the installer
(boring with a custom-package selection ;)
Passed to test lab to verify.
verified in test ...
*** Bug 12857 has been marked as a duplicate of this bug. ***
fixed in internal build for next release ... thanks for the report!