Unfortunately, Magix makes it is virtually impossible to contact technical support in the menu maze.
1. I attempted to render in Vegas 18 a video project previously prepared in Vegas 17
2. I chose, as usual, the format ( this time mp4)
3. Clicked on render, while preview windows showed action that was supposed to render, no dialogue box appeared
4. Left it running as the graph at the bottom indicated percent completion.
5. After about four or five hours the process was completed (in Vegas 17 it takes just over an hour)
6. Completed "rendering" contained nothing except - about one hour long blackness.
Rendering the in Vegas 17 took 67 minutes and was what I expected. Luckily I kept back up Vegas 17 project as, based on my previous experience with Vegas, the software is not forward compatible.