To create a custom keyboard layout for Oolite on Ubuntu:
mkdir -p /home/jonny/.Oolite/AddOns
chown -R jonny:jonny /home/jonny/.Oolite
gedit ~/.Oolite/AddOns/keyconfig.plist
Download the Key Config tool extract it, open the web page and generate the keyboard layout you want. Paste the output into the ~/.Oolite/AddOns/keyconfig.plist file.
For reference the default keyboard layout file is at:
/usr/lib/GNUstep/System/Applications/oolite.app/Contents/Resources/Config/keyconfig.plist