I know that if you use the centerprint function without inputting the variable for time then it will last forever.
registerOutputEvent("GameConnection", infiniteCenterPrint, "STRING 150 200",0);
function Gameconnection::infiniteCenterPrint(%this, %string)
{
%this.centerprint(%string);
}
And then bottomprint is just as easy.
registerOutputEvent("GameConnection", infiniteBottomPrint, "STRING 150 200",0);
function Gameconnection::infiniteBottomPrint(%this, %string)
{
%this.Bottomprint(%string);
}