Well, in your case forget the standard edition. The lowest version where shader works is the commercial edition. This edition costs ~ $ 200,-. The Sphere-Plugin needs at last commercial edition and costs $ 30,-. I suggest you to buy commercial edition for learning.
It also has network-support for four players. AFAIK there are some network-plugins in developement around the forum for more than four players.

EDIT: The Sphere-Website: http://matt.brightwatch.com/sphere/sphere.htm