attachMovie and setInterval

Hi,
I followed the tutorial about multi-dimensional arrays and attachmovie. I would like to create a similar one but I want to add setInterval so that the attached movies appear in an order with some time delay. Instead of the loop used in the tutorial I used setInterval and clearinterval. However, all the attached movie clips’ _x and_y positions are the same and I can’t send the information in the array to the attached movie clips. When I trace() the text boxes it returns undefined. I need some help in this topic. Thanksss.