How to get tempo to synchronize across multiple tracks (or how to handle MML with more than 16 tracks)?

I used the MIDI to MML converter that I mentioned in another thread. However one of the MIDIs I converted had more than 16 tracks, 68 to be exact. I tried to use the different tracks in order to bypass this limit, however, I had one problem: the tempo. It only affects one track (and all of the channels in it). It changes throughout the track, making it so that the other tracks are off-tempo. How do I synchronize the tempo across the tracks?

SB can only play 32 sounds at once, so there's no point splitting a song into multiple BGMs like that (with 16 channels you end up using more than 16 sounds at once because certain affects use multiple sounds)

SB can only play 32 sounds at once, so there's no point splitting a song into multiple BGMs like that (with 16 channels you end up using more than 16 sounds at once because certain affects use multiple sounds)

Does this go for SB4 too?