Q : I run Vista and netplay doesn't work.
A : Caster is known not to work under Vista due to gremlins. The program uses some funky voodoo magic memory hacking to send and receive keypresses to and from IaMP. The security in Vista simply doesn't allow that and thus breaks caster. It's possible that some future version of Caster will patch the exe directly but for now Caster won't work under Vista.