I have been modifying the Agora Less stylesheet to include: gray (normal) buttons which where lacking, and disabled versions for all colors.
The result can be seen in this example page: http://dl.dropbox.com/u/30377416/design/agora-design/gray-disabled-buttons/examples/buttons/button-disabled.html

I have pushed the changes to GitHub in the following pull request: https://github.com/wikimedia/agora/pull/1
Although I tried to use git-flow as it was suggested in the documentation, I ended up using plain git commands to submit the changes since I was not aware of the git-flow command to download an existing remote branch and update it. 
All information I found on git-flow was about creating new branches from scratch, not on how to improve work from others. It would be great to have some command examples illustrating this in the repository documentation.

Pau

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Pau Giner
Interaction Designer
Wikimedia Foundation