i.e. use con tools or something on an rb3 file to see a preview vid of the chart. Don't need to make any edits, it just takes a while for my 360 to load since my USB stick has like 3000 songs on it, so I want to quickly visually scan charts on my computer to see if they look OK before I bother putting them on my console.
Edit: To be clear, I mean to view other people's rb3cons. Not my own. I won't have any project files.