Many script details emphasize the point that Tiger is supposed to be a Persian cat, describing his recessed nose, his proud lineage, and talking with a Persian accent. Yet, the animated cat is clearly Siamese in design.
(at around 1h 9 mins) After crashing into Gladys' house with Dwayne's van, Dwayne begins to regain conscious, and breaks his back as he reaches out for the animals just they escape back to the woodland in time. Yet when he and Gladys arrive with tools to fight off the animals, Dwayne appears to be fine.
(at around 13 mins) When Verne first left the group to cross the hedge, he came out in a backyard. However, when he returned to the forest, he entered the hedge from a road, but ended up in the same place he left from, in front of the group.
RJ caught the grappling hook on a root and left the hook there after pulling himself up. Later, the root disappeared, and although RJ never returned for the hook, but left for the town right away, he still had the hook and used it several times.
(at around 40 mins) When Verne and RJ are fighting over the wagon full of food and RJ falls to the ground, Nugent's chain is not in the picture, but when RJ starts to stand up, the chain is underneath him.
(at around 41 mins) When Verne is trying to return the food to "its rightful owners" and pushes RJ into the ground, there are no toys near. Yet, in the following scene Verne appears, the two toys appear 2 inches from his feet.
(at around 1h 6 mins) When the animals are in the Verminator's truck, RJ tries to enter through the driver's side window, which is closed. Yet, moments later, when trying to escape Vincent, RJ jumps in the broken passenger side in, and is tossed out the now open driver's side window, even though nobody had opened it.
As RJ with the food for Vincent sadly watches Verne and the others be loaded into Dwayne's Van after having supposedly betrayed them, he's at a cliff near some woodland not far from Gladys', and it's not long before Dwayne's Van arrives on a road right next to the cliff, where RJ drops the food for Vincent in front of the van, releasing the animals from their cages and leaving Dwayne lying unconscious. Yet it takes longer for them to drive back to Gladys' while getting away from Vincent at the same time.
(at around 18 mins) When RJ opens the bag of chips, it creates a large puffy cheese cloud that can be seen from space, like around Seattle. (at around 1h 12 mins) However, when the Depelter Turbo activates, a beam shoots out into space, but it comes from somewhere near Chicago.
(at around 2 mins) When RJ first sees Vincent's cave, it's atop a sheer, vertical cliff (so sheer he can't climb it and has to use the fishing pole to gain entrance). However, moments later, when the wagon of food gets bumped out of the cave, it bounces down a more sloped hill with lots of ledges and rocks.
The gang wouldn't have been able to bring the items through the hedge easily, judging how big they are and how small the branches within the hedge are (which the animals judging their size are able to get through alright).
(at around 1h 1 min) Stella and Tiger get into the house, even though they didn't have Tiger's collar to unlock the cat door. This is because the collar was left by the cat door to keep it unlocked while the animals sent the food out through it.
(at around 1h 1 min) When Stella re-enters the house upon hearing the emergency, her white stripes mysteriously reappear, exposing her true species to Gladys, and showing to Tiger the Cat that she's really a skunk. However, the reappearance is no mystery. When Stella comes through the cat door seconds earlier, there's a puff of "smoke" -- which is from the charcoal dust that was used earlier to hide her stripes.
When RJ left Vincent to save his friends from the Verminator's Van, the collision with the cart of Food for Vincent sends Dwayne unconscious, and freeing the animals from their cages, yet, when that happens at the start of the film, nothing happens to the vehicle that crashed into the food.
During the climax while hiding from Vincent on one side of the hedge and Dwayne and Gladys on the other, Dwayne is able to shock Vincent on the other side and gets attacked back, believing it to be the animals in the hedge. Why would he think that, since such as slap can only be done by a bear, something much larger.