The same thing happenned to me while trying to post previously (editing aspect of data), not a good thing for this site.
See below for filesystem clarification (just adding missing data):
**sh-4.1# pwd
/
sh-4.1# ls
automake dev initrd lost+found opt root selinux tmp var
bin etc lib mnt proc sbin sys usr
sh-4.1# cd /mnt
sh-4.1# pwd
/mnt
sh-4.1# ls
home +mnt+home+puppy528-005+virtualbox-4.1.14.sfs sda1 sda5 sdd1 sr0
sh-4.1# cd /mnt/home
sh-4.1# pwd
/mnt/home
sh-4.1# ls
boot general_downloads netbootmein puppy528-005 Slacko-5.5.4G
dsl java puppy511 puppystudio VirtualBox
fonts lost+found puppy525 SAVEMARK wary512_empty
sh-4.1#**
I don't understand when you said above "try this" and there's a greyed text afterward (first entry of yours of the last 3 ones).
I copied+pasted the menu.lst entries as you suggested, maked sure I took out that "/" after dsl.
I now will to reboot & try it, posting afterward whatever happens...happens...
Edit: Before I rebooted I saw your last post/edit/comment & took remedy action at once; meaning that I inserted the "/" after the "=" sign at <knoppix_dir=dsl/...> entry.