no se puede visualisar el contenido (en texto) de los bloques (can not display the content (text) of the blocks)

I wonder why the text is not displayed within blocks

see here https://groups.google.com/d/msg/mitappinventortest/MKYPU6H7xww/Pv8rcOik0-0J

PS: please use png or jpg format for your screenshots next time. thank you.