Listen and Type

I really like the new Listen and Type exercises. They really make you think about the tones and, after only one lesson, I feel they will be really beneficial. My tendency to ignore tonal mistakes when reviewing vocab always leaves me feeling somewhat guilty about marking words as correct when running through flashcards.

When doing this exercise for the newbie lesson, "What's Up?" I got the tones correct as well as the majority of the pinyin. But for some reason I still got a score of 0/4. The spaces between words were all wrong. Is there some rule for when to put a space between words in pinyin? I've wondered this for a while, but never managed to identify a pattern at all. For example:

Phrase 1
hai2hao3 (incorrect)
hai2 hao3 (correct)

Phrase 2
zen3me5yang4 (correct)
zen3 me5 yang4 (incorrect) 

If there are no rules governing the word spacing and spaces are used purely for the sake of readability, would it be a good idea to put a space between all the words for the sake of the exercises?