Hello
some super fast replies
115.2k is what avr studio expects, to change that is a bit annoying so i left it like that and I can communicate with the board no prob
(if you connect with a terminal emulator you can see the programmer responding with a prompt to change the version number reported)
i can write to the chip but it's not 100% reliable yet
test.command is actually wrong because uisp doesn't support the stv500v2. I made another script that uses avrdude
something like this
avrdude -p m168 -b 115200 -c stk500v2 -P /dev/cu.usbserial-A4000QpS -e -U flash:w:bl.hex
but avrdude gives strange errors while handling the fuses.. i've wasted days of work because of that.....
I did compile the bitbang by recompiling libusb and the special version of uisp that guido made but i never actually tested it
because i thought that getting the arduino board to be an ISP itself was more interesting
also the bitbanging is slow (as stated on the website)
from here to a completely robust solution there is still work to do... but for now it was good enough for me. now I have to concentrate on the BT and Ethernet boards 
massimo