okay, alter my last comment, what u need to do is build the first barricade item thing, and then a pop machine next to it then start the round. hop onto the little barricade thing then the pop machine and DEFEND URSELF!!! stay in 1 spot. if u move this glitch will break. if the zombies bust the machine, u should still be flying. otherwise next round delete the pop machine and little barricade thing.
for the ladder glitch, there is another one that u can expairament with, it is the object glitch. if u run off the side of a ladder while having a large pop machine under you the removing it and getting all ur money back, u can float in places NO MAN HAZ EVAH FLOATED BEFORE!
small tip, u know how the first tower, the Dart Monkey, can convert into a spike thrower? Well set him up on the long run trails and set the unit he attacks so it aims down the path. This here can cause him to be one of ur best units.