Haven – “Do not tempt the desperate” [Campaign 3, Mission 3]

Hello, comrades! I have a question, or rather, a bunch of questions about this mission that's been giving me trouble. The problem is that when my hero enters the territory of the city that needs to be captured as part of the quest (and, as I understand it, there are two ways to get into the city: cross the ford or sail in on a ship), the following happens. The hero, a snake, crawls towards the gate where another hero, also a snake, is standing. He stops a little distance away from him, near some stones, and that's it. Nothing happens. The game freezes, and even the escape key doesn't work. In this regard, I have the following questions: 1. Here, people are writing about some altars where crystals need to be brought. What altars are they talking about? 2. They also mention an engineer's house. What is this house? 3. I have the impression that the game is glitching. I would like to know how many quests there are at the beginning of the mission. I only have two: find the Tear of Ash and capture the city. It seems to me that there should be more! Please help me understand what's going on. Thank you in advance!