Although i understood most everything going on in Myst 5, I never figured why there were periodical earthquakes in all of the ages. Were they supposed to be collapsing like Riven? Can someone shed some light on this?

The only area that's supposed to have earthquakes is the Great Shaft... I'm not sure what may have been causing your screen to tremor anywhere else.

This happened to me once. I linked out of the cavern during an earthquake, and was surprised to see the earth continue shaking in Direbo. The earthquakes (complete with sound effects) happened whereever I went in any of the ages I had access to. It was more than a little annoying, but they stopped when I quit the game and restarted it once again. Now, I kinda wish I'd saved that particular game to see if the earthquakes were saved as well. Never has happened since...

It once happened to me at the very end of the game. The earthquake continued throughout

Talking of earthquakes.....

I like it how the screen shakes, you hear rocks falling, but there isn't anything seen.

I think they kind of missed that slight detail out.