Thanks for the feedback!
The game has had a persistent sensitivity setting from the first version in the control tab in the settings - maybe you missed it? Let me know if it's not working as intended.
The performance is sub-optimal, I agree, but in my tests it has generally been playable on a 1050Ti. I have quickly made some performance improvements and posted the updated version just now, but I will try to take a closer look as well soon. Check out the current version, and let me know me if the problems persist. (if they do, please share more details - framerate (F3 during a run to show) with shadows on and off, your CPU and RAM)