Hot Game Secrets:
1) How to easily challenge high levels (such as 15) :
create this fly traps:
http://img87.imageshack.us/img87/4045/traps.jpg
and you'll catch all the green dots !
2) Why you can't use M button to get further than 19'th level :
with "Trap" tactics you'll be able to get higher than 21'th level;
because of the big amount of green dots game will become unstable
and you'll see crazy green dots eating your white dots
even in the best case you'll complete 1-2 levels.