Very glad to hear you liked it.
The question of how and when answers should be locked in is one of a few major gameplay aspects I still don't know how to approach. In the full game the structure of the investigation complicates things a lot, since it will have multiple scenes, with multiple sections each. Right now I'm leaning towards the way I used in this demo but I'm open to ideas.
And yeah, like I've said already, the confusion with the logged-at-start case pieces is because they are there as a bandaid solution. In the real game you encounter the people and things yourself so you're more familiar with each.