Update 19 July 2016: Please note that this should not occur with Generative Components Extension SS6, the following advice relates to earlier versions.
I am running my applications completely offline, with no internet connection whatsoever. And while I've been able to run AECOsim Building Designer in this mode by checking out a license, when running Generative Components Extension the activation will not "stick". Therefore, I am continuously prompted to reload my license. I don't recall this happening in the past when running the Generative Components Extension with MicroStation.
While Generative Components Extension is a free application, a license is only included when MicroStation is also licensed. Bentley Systems will be revising this in 2014 so that each AECOsim Building Designer license will also include a license for Generative Components Extension, allowing both to be checked out if needed. In the interim, you can contact Bentley Technical Support and request a term courtesy license for Generative Components Extension should the need arise.