You can still play them... the code I posted polls the playback routine as a condition to stay in a loop (typical use: a demo that ends when the music finishes). If you don't need to test whether the midi is playing in this fashion then you won't suffer the slowdown. However I would still avoid midi simply due to you having no clue how the music will sound on any one machine.
Most sound cards come with some sort of .WAV recorder. You can usually set these to record midi output, so getting a .WAV of your midi files should be easy enough (just hit record then start playing the midi file). After that you can use DBPowerAmp (a free utility) to convert the .WAV to .OGG (a free lossy compressed format supported by Blitz).
Most sound cards come with some sort of .WAV recorder. You can usually set these to record midi output, so getting a .WAV of your midi files should be easy enough (just hit record then start playing the midi file). After that you can use DBPowerAmp (a free utility) to convert the .WAV to .OGG (a free lossy compressed format supported by Blitz).