Test-Driving Linux Mint 10 "Julia" RC (part 2) USB stick

After installing a Live CD of mint-10 "Julia" on my usb stick 4GB using inetbootin  ; I decided to go for the full installation, but still on the usb stick (not on my internal HD that still contains mint-8 "Helena").

First thing I did was my backup using "mintbackup" (just in case something would go wrong, better safe than sorry).

And then burned the mint-10 "Julia" RC iso file on a cd - boot from the live cd (a lot slower and noisier than from the usb obviously) and launch the install.

After 15-20mn the installation was complete, I checked the result:
the USB stick had 2 partitions :
/dev/sdb1 3.8GB as ext4 (0x83) and still 1.1GB available !!!
/dev/sdb2 236MB as swap (0x05)

At this stage I was delighted and impressed so I rebooted pressed F9 and selected USB Hard drive in the bios menu. But then big disappointment there was only a black screen in text mode with a blinking cursor.

I shutdown removed the USB stick put it aside and started again but then something more serious happened -
a message

"grub rescue> error: no such device : fbbba5b7-8624-a5d3-4e561-ebdf2113311" 

appeared and it made no sense
because it was the uuid of the USB key ?!

Anyway I put the USB back, pressed alt+ctrl+del - and then ... I could see a grub menu offering to boot from 2.6.35 "Julia" or my old 2.6.22 "Helena"
For some reason the installed wrote something on the internal HD to include a call to the grub file of the USB key
and couldn't boot otherwise the USB key was in.

And the worst was that the USB key alone couldn't boot - that sound really strange.

The situation was I could still boot "Helena" or "Julia" but assuming the USB stick was plugged permanently on my laptop - and I couldn't used the USB on another computer because it wasn't bootable ?! 

I asked for advice on irc and got the answer that :
a- when performing an install it's better to remove internal HD of the equation (disabling it from the bios (which a couldn't do with my current Bios), or simply physically removing it (no way))
b- I could probably fix the grub and everything should work fine afterward

I thought to modify the file menu.lst - but discovered later that now the file used by grub is now grub.cfg and that we're not supposed to modify it manually.

to be continued ...