I was also terrified by the save-losing issue earlier...
Thanks god that it's just about some unknown changing of savepath.
I copied my old savefile to the new folder. Problems solved.
Do backup your savefile. It's never over-emphasised.
thatguyyaknow had showed a way to finish this game easily.
Then firestorm977 leaked a tricky style, which is soooo balance breaking. LOL
Put a Tack Tower in the first corner. Use the "tab" trick to make its speed supersonic and its range two grades larger.
Since the attack won't be able to reach that far, two grades of range could be enough detecting incoming balloons.
Your cash should be minus now, but this is far more than enough until there comes white balloons, I guess.
Doesn't matter. Two Tack Towers can simply blast them all. The End.