there is no toad and the worlds are mixed from the basment to the first floor where the normal worlds would be in the final version.
when you get inside the castle you notice that the interior is slighty different than in the final version. also there are no sign posts to read in this beta version and the peach to mario letter is still the same in this version to.
Hello there appears to be various beta version for mario 64 and one of them has the clock replacing the stained glass picture of peach in front of the castle.