When I was a kid, I noticed only two bloopers: the classic end-credit rolling sequence when Jonathan Frid, out of costume, walked through the shot holding his apparel, realizing what he just did, stopped momentarily, and then continued walking through, because what else could he do? The other was when Mr. Frid accidently named the wrong year when speaking a line. I didn't notice any other bloopers whilst a wee widdo one watching the series.
Gerard