Oops, you've just found a hole in our upgrading algorithm
When you un-install, your data files are left behind. The 2.3 installer checks for the presence of the Awasu *software* when deciding whether anything needs to be upgraded. Because you un-installed 2.2, the 2.3 installer didn't find anything and so didn't upgrade anything. But then when 2.3 starts up, it finds your old data files, which are still in the 2.2 format, giving the error you're seeing.
The easiest way to fix this is to un-install Awasu *and* remove your data files. These will probably be in a <tt>Users</tt> sub-directory in the Awasu installation directory but depending on what you've been doing to try get things working, you might also find a set in your <tt>Documents and Settings</tt>
directory. Delete everything and then re-install 2.3.