Thanks for the info. The black screen is because it can't find the tracker. It's to prevent the jitter associated with tracking problems from making people sick. Heaven knows I've had my fair share of headaches thanks to it. The reset function assumes the positional tracker can see the rift. In the future it will handle tracking loss by switching to AR instead, but that didn't make it in time.
In my personal setup I use a IR-black cloth stuffed under the tracker to block out my monitor, and I've got more of it draped on the walls to block those out. I'll add this as a suggestion in the readme and download info. In future versions you'll be able to customize things more like where the tracker is, to avoid problems like this.