How does this actually work? I have no Windows machines so I can't try it. Does it give you a list of demos in your folder to click on to play or something? I read on the projects page about using it as the default program for .dm_68, that's a damn nice feature!
To answer your question, no this isn't for Linux/Mac machines. It is a simple native Windows application that lets you click on a demo on the forums, and downloads it, launches UrT, and plays it, all automagically. The main audience is our referees who watch 100's of demos a week. It saves times, it saves patience, etc. The way it works is basically this.
1. Referee clicks on a "Demo for Review" on the forums.
2. Browser asks him/her if they want to Save/Open the file.
3. Referee clicks Open, and their job is done.
4. Tesla's magic takes care of the rest, UrT launches, demo plays, no further steps by Referee.