How bad is it?

Roller cam = GOOD! You can forget all the cam break in stuff since you have a roller (no break in needed for roller cams)....so that is good. Like others have said, use straight water when you refill the radiator until you are sure you have no leaks (water is easier to clean up if you do have a leak). As long as the temps don't go below freezing you'll be fine with straight water for a while. Assuming you didn't hydro-lock a cylinder and break something, you should be good to go at this point. Oh, and yes, tossing the cork fore and aft gaskets and laying down a bead of silicon is the correct way to install the intake.