Since players can read the Keeper Action cards this isn't really a spoiler... in Scenario 5 the witches summones with the Witchcraft card just pop up for one turn then disappear.  That leaves me two questions...

1) What the heck is that trying to represent?  I sold it as ghosts or something just appearing and disappearing...

2) Do witches appear in any other scenarios where they are not temporary becuase of the Witchcraft Keeper card?

 One appears as a named monster in one specific version of 'Classroom Curses' I believe in fact multiple versions of that scenario lead to the appearance of Witches, in a non-temporary fashion if that helps.

 I think it's supposed to be the witch astrally projecting herself, or the investigators hallucinating, or something (depending on the story).

Is there a limit to the number of witches that can be summoned?  I believe the box only includes two witches, but I don't see anywhere where you can't summon more than one (or two or three or X) witches in a turn (other than they all disappear at the beginning of the next turn).

Rodzilla68 said:

Silly things those rulebooks:

"Monster Figures: The keeper may never have more monster
figures on the game board than those provided in the game." (p. 25)

Weirder still, found under "Component Limitations" heading.