If you already purchased V1 before the actual V2 launch, feel free to mail us for your free upgrade 
@GigasightMedia: Please talk to us and we will help you out. In the past we always gave support for our products and even implemented new features.The Nebula is tested with all the supported engine versions with no known problems! We apologize for any issue and want to go deeper into to solve it, but we need your coorparation to get this done! Most of the users had a good impression of the package. The code is structured and commented, otherwise Epic wouldn’t approve the package for release. The additional code plugin is NOT required as it just adds some minor features like saving a cubemap to disk. On the other hand, maybe you think too complex, the Nebula is plug’n’play and is used with very less controls (e.g. there is no need to touch the Nebula’s Blueprint code).