kboy:
1. is the midid track triggering an external synth? If so, cable up the audio outs of your synth into your sound card. You can then record the midi onto an audio track set to the input corresponding to where your synth is plugged into.
Or, once you have the cabling set up, create an aux with the proper physical input set. Then, with the audio from your external synth being routed into Logic's audio stream, your external synth will be included in bounces.
2. Track automation.