I played it a bit and I must say that it is very difficult to get ahead, to understand what to do and when. Finally, just now, I peeked into the walkthrough / hints provided here, and I found it a bit disappointing to see that you - or at least I - could not get anywhere without these hints. E.g. who could have known that talking to pizza girl has an importance, an importance that the walkthrough points out "Unlock pizza girl as quick as possible".
I would appreciate if there were ingame hints on how toplay.