Add the 11.0 repo and try it that way. If it need loads of dependencies
it could be a problem. You would want to install the 11.1 of any
dependencies. That way you just end up with LXDE being the only package
you install from 11.0 and so removal will be easier.
You could download the .rpm from the 11.0 repo too and install with
that, which should be fine if there is not a list of dependencies.