I have used MIDI2ABC quite often to convert tunes from Mudcat DT to ABC so I could play them on my PC speaker (using PlayQABC), since I don't have a sound card here at work. There is an option to specify the number of pickup notes, which I have used successfully. Of course, you have to guess at it, if you don't know the tune, but it's usually fairly obvious from the lyrics of the song. And even if you get it wrong, the song still sounds the same.

Incidentally I have since found a DOS program, MIDIPLAY, which will play a MIDI file on the speaker (one track only). I got it from the same page as MIDI2ABC, from a link on the ABC Homepage.