Ah, look at your OnActionSe
rverside
Also it should be player.nick = params[ 1];
Another thing, your way may work but I usually send the the players account in a param and then reference it to that to change player vars. More thurough I suppose.
Eg
PHP Code:
triggerserver( "gui", name, "Foo", "Bar", player.account);
Then serverside do
PHP Code:
function onActionServerside()
{
if (params[0] == "Foo")
findplayer( params[2]).nick = params[1];
}