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VST PlugIns and
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I am a bit confused on how to best set-up Pristine Space to work with mono or stereo source tracks.  Would the standard approach be to use one stereo impulse file for a mono source, and two stereo impulse files (Left-Right) for a stereo track??  Or, is a single stereo impulse file the standard approach for both mono and stereo sources?

I guess yes, stereo impulse can be used for both mono and stereo sources.  There is "true stereo" reverb approach, but it requires 4-channel impulse files for processing stereo input.