Is it necessary to use a vinyl sealer if I am going to glaze over a stained maple surface? I will be using Krystal as the topcoat. Can I just seal with Krystal, glaze, and topcoat with Krystal?
If you are using a Campbell glaze right out of the can, then you need a vinyl sealer, glaze and then a vinyl washcoat. Krystal over the top.
Some wiping glazes specify that you sandwich it between coats of vinyl; some don't. Wiping glazes with a long oil content will cause wrinkling if you don't put them between coats of vinyl. Wiping glazes with a urethane binder can be used between coats of CV (e.g., the wiping glaze from Chemcraft or Valspar).
If you want to use the glaze to accentuate the grain, the coat of finish you use to seal the wood should have a low solids content (e.g., 5%) so it doesn't fill the grain too much. If it's a spray glaze that etches the finish, then you don't need the vinyl.