It seems \DBUtil and \DB Query builder generate syntax incompatible code, only \DB::query('...') works good. So, migrations don't work too. Now, I created two tasks up and down for improve database schema and for reset it.
I've been working to separate everything, which is done in 1.8/develop. It has a separate schema class per driver, which DBUtil uses for platform specific SQL.
But as I wrote I haven't gotten around to doing SQLite yet.