Why did Zada leave after season 1?

Funny you should ask- I was just rereading some old Amazing Heroes magazines and there was a short blurb that said Ramy Zada was not liked on the set and was let go because he was "not being much of an ensemble player." Other actors considered to replace him were Parker Stevenson and Michael Woods, before they ultimately selected Bruce Abbott.

I had heard that when they moved filming back to the states, Zada just decided not to come along.
Trying to remember here, where was the first season filmed?