Comment 4 for bug 1164486

You need to pin the version in your buildout config. Look at the 'PICKED VERSIONS' that get printed when you run bin/buildout and that you pasted above. Open buildout.cfg in your editor and look for a [versions] line. If you do not see it, then add a [versions] line yourself at the bottom of the file. Paste the list of picked versions there, change the cssutils line to refer to version 0.9.7b3, and run bin/buildout again. The result should be that buildout does not print any picked versions anymore, because you have now pinned them in your buildout.cfg, and 'bin/instance fg' should start up correctly now.