Getting started with Javascript API

I've just purchased "professional" with the aim of automating some of my routine tasks using the Javascript API.

I've setup a basic project, have confirmed that the "DraftSight API Service" is running and managed to import library files (eg: djConnect.js) from the local web service.

When I try to run a script the it gets stuck on the first step

... .getApplication()

returns an error 'dsJServerError: jsServer connection Failed'

Unfortunately my debugger doesn't give me much more information than that... I guess there is some issue with Draftsight instance??

Any help would be much appreciated!