Ugh, that sounds like what happened to me. I tried to install Mandy 9.1 numerous times (it was my first distro). I'd go thru the whole process, make a bootdisk, get ready to reboot, and [deflate] no hard drive boot. Then [deflate lower] the boot disk would freeze on L and begin to display 01 01 01 01 01....
I didn't have nearly sufficient experience to fix the problems. I wish I could be of assistance here. I thought I read something about updating "drakconf" after installation (but before reboot) to resolve the boot disk problem. I can't remember where I read it however, so I may be giving garbage advice. I couldn't test updating to combat the bug, since I didn't have a web connection.
RH solved my Mandy problem. Someday, I'll learn how to get 9.1 working though