this is Michaela's Guide, it should make things much easier where you are stuck! Steam Released Guide
Actually I just redownloaded it after I replied to you and did one of the boys' paths. Diana's showed up after I got back to the Main screen so Its only one of the boy's paths.
The demo requires the Boys Stories (as far as they go) to completion before Diana is unlocked. The Full Version can take Diana's route from the start; if I understood what was said over stream the other day