Hi -- thanks for the response. Yes, the sound changes to the VST's default sound for midi channel 1 when I try to "Export to wave file." If I try to "Merge audio and DXi tracks to stereo wave file" then the sounds themselves are intact, but the rhythms are wrong and there are notes missing -- strange.

Re-route midi to default synth is enabled (going to Halion Sonic).

GS Wavetable isn't showing up as a midi input option (using Presonus Firepod). It's available as a midi output...