To spare you from some of the wrath of the forum
a) yes, it is laggy for most people- it\'s not really \"Lag\" (which is a network phenomenon) but really low FPS - the size of the level is very hard for the engine to handle at this point. Hopefully future versions will improve.
b) A lot of people will jump on you if you ask questions without using the \"search\" feature - searching for lag or looking in the \"top ## newbie questions\" threads may answer some other questions.
Thanks, and welcome to PS!
Daniel