Continuity mistake: The skins that Dr. Marshall and Will find when they go to rescue Holly are out of proportion and don't even look close to how the rest of the sleestak are shaped. Even though it was a "shed skin" - it doesn't even have the same patterns on the legs and arms as the real ones.
Continuity mistake: When Holly is translating Chaka's talk with Will around the campfire, we see the closeup shots of Holly showing her right hand holding the bottom of her notebook while she is writing in it. In the closeup shots of Chaka and Will, her hand is up underneath the book curing over the top.
Continuity mistake: When Dr. Marshall is running towards the catapult with the Nitrogen tank, we see a shot from under the catapult with Rick but no dinosaur behind him. Given the relative flat layout of the land and height of the dinosaur, it's clear they forgot to add it into the scene.
Continuity mistake: When the 2 dinosaurs smell Rick by the ice cream truck, they are at most 100 feet from them. However when we see Rick catching up to Chaka, the dinosaur is now several hundred feet away, catching up.
Continuity mistake: When Rick goes to pour pee on himself, the face of Will's watch is more on the side of his arm. When the camera cuts back the watch is now facing up from his wrist again, only to go back again to being on the side in the subsequent shots.
Continuity mistake: When the dinosaur slobbered on everybody in the cave, they were covered in heavy slime. In subsequent shots, with no time or means for anybody to clean up, the slime was almost entirely gone.
Continuity mistake: When Rick Marshall douses himself with dinosaur urine, the amount on his shirt changes between shots.