The Pictogram feature on DAU is quite simple. As per the install guide: 

 

If the unit is not operating in this manner check setting P121 = 1 (EN81-28 compliant pictogram mode). Send the following SMS to set this: Pin1234,P1211

 

If you find the pictograms are not functioning as shown then this would indicate a fault with the unit, and the unit should be replaced and returned to Barcelona