See Stackoverflow question http://stackoverflow.com/questions/11912788/importerror-no-module-named-flask-ext-security-datastore-sqlalchemyuserdatastor, looks like the example app was calling an older API?
example app had a problem, see http://stackoverflow.com/questions/119…
This is because you're using the code from the example app in the develop branch. It will not work when you install Flask-Security from pip with pip install flask-security.
pip install flask-security
If you want to use the code from the example app in the develop branch, you need to install flask-security with pip as such:
pip install https://github.com/mattupstate/flask-security/tarball/develop