I have the same issue

Webmaster-Mac-Pro:adapt_authoring benjisan889$ grunt server

Running "copy:main" (copy) task

Copied 14 files

Running "less:dist" (less) task

File frontend/src/adaptbuilder/css/adapt.css created.

Running "handlebars:compile" (handlebars) task

File frontend/src/templates/templates.js created.

Running "start" task

dyld: lazy symbol binding failed: Symbol not found: _node_module_register

  Referenced from: /Users benjisan889/Documents/Sites/adapt_authoring/node_modules/connect-mongo/node_modules/mongodb/node_modules/bson/build/Release/bson.node

  Expected in: dynamic lookup

dyld: Symbol not found: _node_module_register

  Referenced from: /Users/ benjisan889/Documents/Sites/adapt_authoring/node_modules/connect-mongo/node_modules/mongodb/node_modules/bson/build/Release/bson.node

  Expected in: dynamic lookup

Trace/BPT trap: 5

Anybody have any suggestion of how to solve this, please