I just brought up a new system with the very latest (12/23/2002) livecd iso image, but I only used the stage1 image to install into a chrooted partition from a RedHat 7.2 system (which will soon be wiped). I started bootstrap script early and wanted to cancel. Hitting Ctrl-Z stopped the underlying processes, but the main bootstrap script was still R in the process list. The other tasks all showed T, and kill -STOP of the bootstrap script (from another console) finally gave me the bash prompt back. Continuing is just a simply fg, but this took several tries to get the scripts stopped in the first place. In the meantime, the outward appearance is that the script has hung; you can't get a prompt. This behavior was trivially reproducible for me.
This is now fixed on cvs and will show up on rsync within the hour. we were trapping the TSTP signal which was what was causing the problem. ^Z et all work with the new script now. This bit me too! :)