Played several times on regular difficulty. Played first with version 1.59 and again with the latest release candidate 1.60.
A mission like this is a nightmare for a beta tester because of the amount of mandatory cutscenes that must be viewed in order to progress. But, my first play through, the immersion was there the whole time and the end came much quicker than I thought.
Much of what I feel about your efforts only reinforce what others have expressed already in regards to your chosen camera angles, music selection and timing, emotion in the voice acting, little details that bring the AI to life and story development as a whole.
The first task to move the crates worked perfectly. No double addactions, no mix up with the phone addaction and all removed as it should have. I played the first time by moving all the crates myself but after moving the 6th, I decided to strike up a conversation with the truck driver. I didn't want to put the rest of the task off on him so I chose not to answer him. Because of that, the addaction replies stayed with the player until I activated one after meeting up with the boys. It would be nice of you to offer an addaction that would simply say "Nevermind" and then remove the other addactions. The other options worked great.
The mission progressed fine from here with only a few hangups to mention. Some of which are BIS related while others can be balanced by you.
Bedges made mention of one of those and that being of the group leaders having NVgoggles and not having them when they die. I remember you discussing this issue in a thread of AI not recognizing the enemy in the dark and so you needed a way to balance that. I agree but I think you went too far and tipped the balance in favor of the AI. Giving the initial group leader a set of nvg is good but I would not equip the new leader when the first one dies. The AI are already supermen once they know of the players position regardless of the lighting. Giving the player only eight shots with that hunting rifle coupled with the AI ability to share player enemy info once they know about him, is quite a challenging combination. Add the fact that the player can't spot units through vegetation or see them in the dark even if they know exactly where they are and the challenge becomes frustrating. By only giving the first group leader a set of nvg equipment, you level the playing field for the player some by presenting him/her with the opportunity to use strategy by targeting the leaders first or expending the long range ammo on them to essentially blind the others. If the player fails to see the opportunity, it becomes his fault. Once the group knows about the player, you can force the leader prone to make his elimination more difficult. If you don't mind the extra scripting and you feel the new group leader should have the night vision when the former leader is taken out, be fair about it and make him get within a meter of the dead former leader in order to get the nv gear. That will allow the player a chance to prevent it and also provide a visual affirmation as to how a unit who did not have the gear before, has it now. Immersion is retained and the player is satisfied.
To prevent the player from using the night vision from dead leaders, you could simply have him say it's damaged but leave it there for him to take. Then just use a script similar to the first person script. If the night vision is activated, shut it off by playing a click sound to symbolize the player attempting to switch it on and it failing.
Another hangup caused by you is the removal of dead in the field between the church and Piotyr's car. I was aware of my limited ammo with that advantageous rifle and so I made it a point to see which roaming enemy had what weapons and made note of where I dropped them. When I reached there position, they were gone and so too were those precious resources. That killed immersion some. Leave them be. If you don't want the player having a particular weapon, remove all but 1 mag when he dies. then the player has to decide whether he wants to push forward well equipped or not. If you're worried about lag...why? You don't have much going on and I don't see you spawning additional enemy.
The other hangup is a BIS one. I can be in the darkest part of the forest and the enemy have no night vision but it never fails that once the leader spots me, his entire group knows exactly where I am out and where I move to. In addition to that, I have no idea where the enemy is in the dark because I can't see them. Even if my AI team mates spots them and engages, I am still left in the dark with no idea which side of the tree to tuck into because I can't see the enemy moving about. You can't help this but you can certainly make it less frustrating by reducing the numbers and coverage area of each group. The areas that I am speaking of in particular are Jergerow's house and the village where the mafia leader and his henchmen are. That silenced m9 is quiet but sucks against a large number of foes because it practically takes an entire clip if you further than 20 meters away. If the louder, more powerful and more accurate(somewhat) AK is used, you're suddenly spotlighted by everyone in the area. For the sake of story immersion, thin out the ranks of the party looking for these troublesome young men and spread their search areas out to prevent mass engagements and overwhelming odds. Add more lighting to the areas by turning the parked car lights on and positioning them toward areas that patrols may be looking in. Using parked cars with headlights on in an attempt light patrol areas are great for immersion.
After playing several different ways, I did notice the subtle adjustments that had to accommodate the various decisions, such as moving or not moving the crates, the results of each answer to the truck driver, the survival or death of Olaf, retrieving or leaving Yuri's gun.
Being nit picky, I noticed that unless the player parks the car precisely where you want him to, the story fails to proceed by preventing his friends from getting out, for example, Yuri's suggested parking spot and in front of the doctor's home.
Just to mention, I thought your workaround for getting Olaf to Kostja was clever. We all know that the AI don't use those castles well and Olaf would have never made it to his brother without the player having to drag him down again. Your decision to have Kostja crawl down the hill side and get caught was a good remedy.
Didn't notice any difference between 1.59final or 1.60RC.