As of May 2014, we've discontinued operation of Bootstrap v2.3.2's Customizer. It's been nearly a year since Bootstrap v2.3.2 was released. Bootstrap v3 was released soon after, and is now mature. We continue to encourage new projects to use Bootstrap v3.
As always, you can of course still build Bootstrap v2.3.2 from source yourself. See the Getting started docs and Bootstrap v2.3.2's README for instructions.