I wanted to give this a try seeing some of the osu!mania results on YouTube, but it did not work for me. My video output only showed the title screen and that's it, unfortunately. It looks like an absolutely fantastic tool, but it looks like I won't be able to make use of it myself.
Output video: https://www.youtube.com/watch?v=7NLPLfAXYd0
Attempted replay: Megitsune 4K MX - 100.00%
Output video: https://www.youtube.com/watch?v=7NLPLfAXYd0
Attempted replay: Megitsune 4K MX - 100.00%