If you are using GrandPrix Race Manager in combination with our RaceReplay software, then GrandPrix Race Manager can control the recording of video and trigger the replay sequence or you can do the recording and replay manually.
Instructions on interfacing the two programs are in the help files for each of these programs. In RaceReplay go to the "Using RaceReplay" section and then to the "Interfacing with GrandPrix Race Manager" section.
If you have problems interfacing the two programs, you can go to the "Troubleshooting" section of the RaceReplay help file and then to the "Video Replay Troubleshooting" section.
We've added a video on interfacing these two programs. There is a link to it on GrandPrix Race Manager's Video page, http://grandprix-software-central.com/gprm/videos.php.
Below shows the setup if running one or two computers: