I also was looking to documentation but on project site it's old version only and no info about 1.0 version or even 0.12.6 . I think it's better to use old stable version (I also installed 1.0 version but had some problems and I'm back to 0.12.6)
I've just found https://github.com/chriseppstein/compass/blob/stable/doc-src/content/CHANGELOG.markdown so it seams documentation is on http://beta.compass-style.org/