Got this when running your buildout so I can't test the generated interpreter:-

Error: There is a version conflict.
We already have: colander 0.9.9
but notaliens-web 0.0 requires 'colander>0.9.9'.

notaliens.com/eggs/PasteDeploy-1.5.0-py2.7.egg',

Does it a typo or really correct path ? Assuming you run the buildout at the root of your project dir, then it should be relative to
eggs/PasteDeploy-1.5.0-py2.7.egg', no ?