USB booting :: USB frugal grub: can't boot

After reading just about the whole wiki and forum, posting my own thread seems like my last resort..

I'm trying to install DSL onto a 256 mb DSL stick for use in a HP thin client (without CD, floppy or HD). When using the default 'Install to USB pendrive -> For USB-HDD Pendrive' option from the DSL 1.5 LiveCD everything goes well.. I get a functional single partition USB DSL image that works on my thin client. Because I have no HD to write to I'd like to use my extra USB space (256 - 55 mb for the Image leaves about 200mb) for my /home dir and for backing up my settings. This can't be done using the mentioned default installer so I tried some other options:

- Frugal Lilo install: won't install on USB
- Frugal grub install: installs but I can't boot from the USB stick (?!)
- Tried to modify the default 'For HDD-Pendrive' script to skip the partitioning fase and manually partition the stick: didn't work

Can what I want be done ? Am I correct that the frugal way is the way to go ? Then why can't I boot ?

Thanks in advance !

original here.