I had the same problem... the solution is to disable debug mode in Joomla! Configuration.
In the CB 1.1 installer the tables are created and then, progressive updates are performed if certain queries fails.
When debug mode is on, the query fails but Joomla! captures the event, and the installer fails.
It's not really a bug, but maybe CB should check DB model in a more "clean" way.
Busman.