Between groups stops after 8 stimuli

Hi,
I've set up 20 stimuli and 20 questionnaires, one for each stimulus.
The stimulus/questionnaire pairs are numbered 1,1;2,2; 3,3;...20,20 in the BGR column.
The random function works fine, but only 8 stimuli/questionnaire pairs are shown when I run the experiment. After that, the 9th stimulus appears and then the screen goes blank.
I've run it several times; all of the stimulus/questionnaire pairs are available to be randomized, but only 8 run at a time.
Plus I never get to my concluding instructions.
If I run the experiment without the BGR function, the same thing happens.
Anyone have any ideas?
thanks,
Irv

Is this v2008? Also, do you have any stray "skipto" values around? Feel free to zip the folder and attach it--I'd be happy to take a look. If you do so, just let me know exactly what to do and where to look for the error.