Perhaps I am the exception, rather than the rule and/or I have not explained my query correctly.
My goal with SLM (or any similar app...of which there aren't any, because it's so amazing) is to simply mirror the way that I perform with a midi keyboard, connected to a TC Helicon Voicelive 2 vocal processor. I dedicate one of my 16 available midi channels in my keyboard to ONLY transmit program changes to the VL2, to switch presets as the midi sequence plays my backing tracks. This eliminates the need for me to play hop scotch with the VL2 and can focus on making the changes to all of my other gear on my pedal board as I play guitar and sing. This system works well, as I have been able to fine tune the program changes, based on the tempo of the song. Being able to adjust the midi timing to the visual grid of the song (displayed in beats and measures, as opposed to seconds) has yielded great results...save for having to bring a keyboard to the gig, just to play the backing tracks.
Since I have recorded the sequences as a stereo audio file (with a one bar intro), the mp3 file should be the same as the midi sequence, as far as timing is considered, so being able to have SLM reproduce this dedicated program change information in time with the mp3 file, seemed like something worth pursuing. I see now, that it's not possible.
Once I manage to get the program changes into SLM (manually) and adjust the timing of the events (which takes quite a while), it works great. My issue is with the inputting of this midi information into SLM.
Thanks for listening.