In addition to the solution of the playlist generator:
Usually, the card should play for the time you specified in the settings. The program switches to a new show, though, when the model "wanders" offscreen (for instance when the card plays in a small version at the right-hand bottom of the screen and she walks back and forth in a scene so that she walks off-screen). I also used to have the problem that the program switched to a new show after walking on/walking off clips (there are a couple of those in older shows, indicated by arrows, no longer in shows since the switch to 3K quality, I think), but that changed with a recent update of the software (at least I no longer have the problem). Maybe updating to the most recent version will be helpful for you as well?