MDVI's development state is still alpha, which means it could crash miserably, display obscene pictures instead of Math text, infest your dog with fleas, and/or bring chaos and destruction into your otherwise happy and relaxed life. This does not mean that MDVI is utterly useless. It should display DVI files correctly, and if you don't use the more experimental features (like Type1 and TrueType fonts), things should go smoothly. It is almost certain that you will find problems and bugs. If you do, please consider reporting what you find or making suggestions for improvements at MDVI's SourceForge webpage (http://www.sourceforge.net/projects/mdvi). The interface still needs a lot of work, but most of the development is currently concentrated on MDVI's guts, which you don't see on the screen.