The SMF (Standard Midi File) format should be ok.
The uTool (mixer) player currently does not support midi output. We are going to implement this in coming version(s)
There’s no tempo settings in LP-16 because the LP-16 just plays out the midi file as it is. So it is your responsibility to create a midi file which has a matching tempo as your audio file(s)
Please use uTool 2.0.055 to create a content for your LP-16.
If you still have an issue please send me the midi file I can check what is the issue with the file