Pretty comprehensive instructions and yes a little on the convoluted
side so you could have made an error somewhere. Interesting that the
Xoom can access Ubuntu and presumably see the file system / navigate
etc. Maybe there's enough difference between the Kubuntu file system
and Ubuntu for the instructions to fail, though don't see anything
that would be that different. Could be an error in the config file
modifications needed.

At least you can transfer files between Ubuntu and your Xoom even if
it's not quite as easy as it could be