Similar setup here.

Which Ubuntu version? Which architecture? Is Ubuntu your host OS or is Ubuntu running in a VM? Which SDK version?

I notice some of my keys don't work either in SDK GUI, and I cannot use setxkbmap because when I do I get error this extension is not available. My enter key doesn't work, for example. When I enable virtual keyboard my enter key pops up the virtual keyboard.

To isolate/workaround/fix the problem:

• Use Python from SDK CLI. No need to use in GUI.
• Update your Python. You are not using the latest version. Maybe your whole SDK is out of date. What SDK version are you using?
• Check if problem exists when you run shell in xterm instead of Python in shell in xterm.
• In Scratchbox (not from X but in terminal of host) to use " see if this works. Now start Python and see if " works.
• From Ubuntu use Terminal, export DISPLAY=:2, execute gnome-terminal and test keys, compare with both host and SDK.
• Install x11-utils in SDK and use xev to see binds.
• Check output of xorg.conf and setxkbmap -print on host platform and SDK. In my case, setkbmap does not work in SDK/Xephyr but you can check if you can fix problem by passing flags to Xephyr.