Headscratchers / Night at the Museum: Kahmunrah Rises Again

• Why is the tablet incapable of telling the difference between real sunlight and picture sunlight? This almost cost the gang their lives.
• Isn't the tablet supposed to do everything in the building? That scorpion should have already been active.
• Why were the hieroglyphs animated? They weren't in the original movie and it's the equivalent of English words animating. The tablet is Egyptian, so it should know to not animate them.
• How does entering the poster get them back into the real museum?