Factual error: When the boys are sent back to the Cretaceous era, they come across a leptictidium, a small, bipedal mammal they call "Leppy." Leptictidium were not around in the cretaceous, they didn't appear until around ten million years after the dinosaurs went extinct, in the early Paleogene. They also lived in Europe, not North America.
Factual error: The saboteur sabotages Raven's business by pouring lots of kernels in the popcorn machine. However, the saboteur pours the kernels into the glass holding box instead of the pot, so the kernels would not have heated up enough to cause the popcorn mountain.
Factual error: When PC Plum picks up a set of keys from the table, Eadie McCredie claims they are her keys for her minibus. She drives an LDV Convoy minibus and the key is from a Vauxhall, a completely different design.