Interesting, never come across this situation before. After some investigation, what seems to be happening is this... In the question T1demo8 you have MediaLab skip to T1demo9 unless the participant indicates "other". This makes perfect sense.

So assuming the subject does not indicate "other" on T1demo8 then MediaLab will want to skip to the next item named "T1demo9". When it finds the item, it is administered. However, by using the secret key combo "ctrl+right" you are asking MediaLab to skip the current question. Consequently, MediaLab skips T1demo9, as if it had never been seen. So on it goes through the remaining items looking for--you guessed it--T1demo9. Of course, it doesn't find it because it's just been skipped and so the session ends.

The code could be modified, but I'm hesitant to do that because it's safer just to say that if you press ctrl+right then the item is skipped as if it never happened. A possible work around though might be to place a dummy item directly preceding T1demo9 and skip to THAT item. Try using a blank instruction item with a duration parameter of (d1). This will allow the skip to execute fully and then allow you to proceed to your real item automatically (with a 1 second delay). You could then skip T1demo9 using ctrl+right with no unusual consequences, I expect.

Hope that makes sense!