Finally, back at this game so many years later, went full 279 seconds, 10 balls! After I was sure I got it, based on music and previous runs, I just chilled and toyed around, went more 79 seconds... maybe that's the catch. And always look at the center and monitor the fastest balls.
Even before i play the game, I was looking into the comments... And now I feel a little sad for the dev. Lots people complaining about the premmium content, and rating 1/5. I think that's not fair enough. Taking 1 star or whatever is a thing, but you're being too harsh. I make programs too, but not games, and I know that it sucks to have you work underrated. Kongregate is a nice site to play things for free, but bought content is fine for supporting, because many players just forget that some devs need incentive, or even help, to continue to do that. Not saying that this one is a fine distribution ammong premmium and free content. Kingdom rush have some extra levels and nobody say a thing about it. Ok, it's one level for each 10 or more free one's, but if the mistake of the devs is not balancing that good enough, he should not be assaulted like that. Sorry if have too many english errors in my comment, not my main language.
For NielssC: On lvl 6 of grisly manor, after the two speed boosters, you take 3 coins in each side and there is a row of coins ahead that kind of asks for 2 wall grips. Well, behind the purple flag that is fixed at the bridge in this part, there is a silver coin. Hope it helped.
The upgrades are expensive, but they can throw out all the game fun if maxed. The chicken thing, for example. On full level (it costs more than 20 thousand to do that, but you can make it for 2 thousand on a offer like today, of 90%), it can pass any challenge without wall grip. And in survivor, it can beat any difficulty from above or from the sides. Its ridiculous good. Pay its price. Needs the new world soon also =D
Man the real trick is to see the colors with less connection points, and start with them on places that only they could go or the more logicals. I finished many levels at first try with this in mind.
 "Incremental Epic Hero 2"){kind=icon}
 "Particles"){kind=icon}
 "Sentry Knight 2"){kind=icon}
 "The Last Door - Chapter 3: The Four Witnesses"){kind=icon}
 "Earn to Die 2012: Part 2"){kind=icon}
 "Seed of Destruction"){kind=icon}
 "Diamond Hollow"){kind=icon}
 "Frontier"){kind=icon}
 "Running Fred"){kind=icon}
 "New Star Soccer"){kind=icon}
 "Theme Hotel"){kind=icon}
 "More Bloons"){kind=icon}
 "Linx"){kind=icon}
 "Cat God vs Sun King"){kind=icon}
 "Penguin Overlords"){kind=icon}
 "No Time To Explain"){kind=icon}
 "Road of the Dead"){kind=icon}