...to customise the 4 buttons and the circle. [...] to customise 2 of the keys, one for shift and one for control, it would be a great help.
This is exactly I managed to do. I'm working on openSUSE 10.3, but I don't think the mechanics are different for Ubuntu. It is an X-thing, which means that the tablet will be configured in the /etc/X11xorg.conf file and /home/yourusername/.xinitrc
Assuming that you have the tablet in a working order already, and it is just your goal to configure the keys, add the following lines to your .xinitrc-file
# Define the Bamboo buttons
#
if [ -x /usr/local/bin/xsetwacom ]; then
/usr/local/bin/xsetwacom set Pad AbsWDn "Button 5" # touchpad scroll up
/usr/local/bin/xsetwacom set Pad AbsWUp "Button 4" # touchpad scroll down
/usr/local/bin/xsetwacom set Pad Button1 "Button 1" # key 1 (<) click left
/usr/local/bin/xsetwacom set Pad Button2 "CORE KEY SHIFT" # key 2 (FN1) SHIFT
/usr/local/bin/xsetwacom set Pad Button3 "Button 3" # key 3 (>) click right
/usr/local/bin/xsetwacom set Pad Button4 "CORE KEY CTRL" # key 4 (FN2) CTRL
/usr/local/bin/xsetwacom set Stylus TPCButton "off" # side switch mode
/usr/local/bin/xsetwacom set Stylus mode "Absolute" # positioning mode
/usr/local/bin/xsetwacom set Stylus Button1 "Button 1" # pentip click left
/usr/local/bin/xsetwacom set Stylus Button2 "Button 3" # Lower side switch click right
/usr/local/bin/xsetwacom set Stylus Button3 "Button 2" # Upper side switch click middle
fi
The location of xsetwacom can be determined by
:~>whereis xsetwacom
xsetwacom: /usr/local/bin/xsetwacom
Saving the file and logging out and in again as your regular user, will restart X and the buttons should have the function you configured.
For testing purposes you can of course use this command on the commandline. In that case you don't need to restart X.
An alternative is to use
:~>wacomcpl
which gives you a rather simple gui. Select Pad>Tablet controls and configure the buttons as mentioned above. Left, Right and Middle speek for themselves. Ring clockwise must be Fifth and Anticlockwise Fourth. For Buttons 2 and 4 select Keystroke>Modifier>SHIFT an CTRL resp.
If you want to change the buttons of the stylus, follow the same procedure for the stylus. Changing the stylus buttons will change the eraser as well and vice versa.
This will have the same effect as editing the .xinitrc yourself, but maybe you will find this easier.
Hope this will do it for you too.
Caspar.