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There was a MicroIllusions-published game/series called Discovery which features that basic premise (opening doors on a spaceship by answering questions). It seems to have been modular (with add-on discs and suchlike), and there seems to have been at least one module that used spelling questions. Here's
something with a few screenshots.

An edutainment game, probably amiga (not sure if it was ported to other computer systems), that was set on a space ship, where you needed to open doors by spelling words correctly.
Can't realy give more at the moment.