Issue with Asset-rack

I get the following error when I clone the repo in cloud9 and run it 

/home/ubuntu/workspace/GoFree-master/node/node_modules/asset-rack/node_modules/less/lib/less/parser.js:418
                        else                                  throw new(LessError)(importError, env);
                                                              ^

[object Object]

worker 2206 died
