Question: How come Alex's parents or any other character from the last movie don't make, at least, a small appearance in this movie? I know that Bernie Mac, who voiced Zuba, is dead, but can somebody explain Zuba and Florrie's fate?
Answer: They don't appear because Zuba's voice actor, Bernie Mac, passed away and their absence was done out of respect for him.
Question: It's now clear why Angus is found in the circle of stones, even though he was afraid to enter it in the first place. There's one part of that matter I don't quite understand, though. Why is he afraid to enter that circle in the first place? Is there something in that circle frightening him? Is there a special effect?
Answer: The stone circle is like a gateway to the spirit world, something slightly supernatural. Angus senses this, and it makes him freak out.
Question: After the saber-tooth squirrel named Scrat was eaten by a shark, how did he get out of it?
Answer: Because he is a survivor and this is a cartoon. There were plenty of other times through the series scrat was put in a deadly situation only to return later. In the first movie alone he was trampled by a dinosaur, electrocuted with a lightning bolt, and frozen in ice until he thawed near the volcano thousands of years later.
Question: Since Blue Falcon is an older character... Is Captain Falcon from the F-Zero games based off him? The similarities are great.
Chosen answer: No. Other then the color blue, and falcon in their names, there is nothing indicating Captain Falcon was inspired by Blue Falcon.
Answer: The Blue Falcon was a Saturday morning cartoon series that ran during the late 1970's.
Question: Is Griffin always naked? Because his clothes (glasses) are visible but he is not.
Answer: There's a scene where he's wearing swim trunks which are visible, but he gets embarrassed when they're pulled down and he runs away. Obviously just meant to be a gag, but if the thought of people "seeing" him naked embarrassed him, one would think he must normally be dressed in clothes that can't be seen.
Answer: They don't make an appearance because they were irrelevant to the story. The decision to go back home would have been made with or without any character introduced in the previous movie, so they were simply not included. Alex's parents would have continued to live in Africa after Alex and the others left.
Casual Person
That makes no sense though because (I know it's a kids movie) but the way they portray it, it makes it seem like Alex doesn't care about leaving his parents and what he just recently realised is his birth home. Like, it feels like there was some necessary dialogue there (probably not for the kids though).