Yeah, please disable the custom cursor. IME custom cursors are something that site designers tend to like, and think are pretty cool, and site visitors end up loathing. The cursor is your interface to the UI and as such isn't exactly a *part* of the UI - it's your way of saying "hey I'm here, I can do things," etc. So for a UI to take hold of it and change it is extremely jarring.
(Video games often do change your cursor of course, and part of that is because they're indeed trying to be immersive, and you're here for that experience. But such is not the case on a website.)
