Late-90's live-action first-person point-and-click
 

This is gonna be a tough one because I actually didn't play much of the game, but hopefully this small segment is enough to identify it.

It's one of those games of that era that incorporated transparent green-screen videos on a static background, kind of like Connections. It was a first-person point-and-click adventure with educational undertones.

As for the identifiable features, the setting of the beginning segment at least was a sort of ancient golden age Venice-type city, what with rivers for streets and everything. You click to move from screen to screen. One of the first people you meet is a tribal-looking two-headed guy. The characters are static until you pick a dialogue option and then their response is a short video clip.

I'm sure this must have been from the 90's, but since I'm not absolutely certain how old I was when I played it I suppose it could've been early 2000's, but that wouldn't quite align with what my impression of the style was. It was on a Windows PC.

By your definition, it's definitely myst-like game. Cryo was a big fan of such games at time, but I cannot found any exactly Cryo game with such properties. Try Adventure Legends? They have impressive adventure collection.

Those are some great leads! I looked up a list of Cryo games and thematically they seem right on the nose with their ancient golden cities. But graphically, they don't appear to use live-action video clips based on the gameplay videos I looked up.

Is Adventure Legends this website here? http://www.legendsworld.net/adventure/news

Yes. Double site now - adventure legends and shooter legends.