Horatio (mod author) hasn't updated the Dawnguard mod in awhile, so it's probably dead. It's too bad because I think it had a lot of cool stuff about it. First of all, the Dawnguard armor looks great and the style fits well with Kenshi look imo. I like the idea of the quest line and the unique NPCs, too.

Unfortunately, there's some issues with the execution. I applaud Horatio's creativity in making all the armor and weapons work in the Kenshi system, but it's very strange:
1) Shields are a backpack item. They give stat modifiers, but don't get used in combat.
2) Gloves use the pants slot - strange but it works when used with the set.
3) You have to use the gloves, boots, and chestpiece at the same time. Technically, nothing stops you from using only one, but it will look bad. There's disconnects in the character rigging so the ankles and wrists don't line up properly with vanilla. If you use all three pieces they do connect properly and it looks great. FYI - I have Community Part Map mod loaded as per the requirements so it's not that.
4) Helmet is the only piece that works fine on its own or with the set.

The big weapons look nice and the animation lines up well with the Kenshi heavy weapons. The small hammers and axes use the hacker weapons and aren't aligned to the character model/animations. They float just outside the character's hand and it looks pretty bad.

Finally, the quest itself is a bit buggy. I ran into an issue after bringing back the three quest characters and rebuilding the fort where I had no idea what to do. Isran would talk to me like normal, but there didn't seem to be any continuation. I don't think the quest just ends there, but I don't know what to do to trigger the next stage.

Anyway, it's a long post to say that some of the assets in this mod are awesome and I think it would be a nice mod to snag some pieces from it for a personal mod, but it's sadly not very playable in its current state.