I spent as long on the last level as I did figuring out how to get on top of the "THE End" letters, only to find that if there's a secret up there I can't see it. :/ Still, great game.
To people with crash errors, the same thing happened a while back. Yes your rank is gone for now, and your cash is screwed up. Go to your achivements, and rank, and friends, then take a screenshot that includes your rank as viewed by Kong, and as viewed by the game, and send an bug report explaining the error and with the screenshot, and they'll fix your account when the server is fixed.
fun fact, my computer or browser or this game reset (even toggled back on the music) to the main screen after I beat 116 rounds and wasn't slowing down. (in progress, not in lag, it was laggy as heck)
kept going in freeplay mode, and I ended up with 8 banana research facilities, the entire first channel lined with sun gods, and a nine by nine grid of max level wizards. I had some more stuff, but the bloons never got to it before the game crashed. :(
i'm stuck on 24, when i jump over the spikes at the bottom right, it instantly kills me, with or without the buff, even before I hit the spikes, even before I warp.
Easter egg; if you hold "s" and right arrow or "d" and left arrow or "d" and "s" or right arrow and left arrow he runs in place and looks like an idiot.
I've seen games with similar gravity manipulating concepts, but none quite so good as this. 5/5 for awesome, the only minor flaw was that i found it hard to distinguish between the portal and what you pick up
 "Down is Up"){kind=icon}
 "Bloons TD 5"){kind=icon}
 "Matriarch"){kind=icon}
 "Bloons Tower Defense 4"){kind=icon}
 "Frantic Frigates"){kind=icon}
 "Warp Game"){kind=icon}
 "Reactance"){kind=icon}
 "Shift: Freedom!"){kind=icon}
 "Epsilon"){kind=icon}
 "Viricide"){kind=icon}
 "Flaming Zombooka"){kind=icon}
 "Toss the Turtle"){kind=icon}