OMG so many fixes, the game was in a much worse state than my testers had me believe!
1) You can read the sign, you need to stand infront of it and press up and interact. I would have liked it been able to be readable from the side but the engine didn't like me doing it when it was side on.
2) Not a secret boss, the NPC kicks you out if you talk to her too much and once the fungal outbreak takes over the town she locks herself inside.
