I have a MIDI file that has each drum on separate tracks (Kick on Track 1, Snare on Track 2, etc.)  I want to put them all together onto one track, but not having much success.
 
I did try dragging each track into the one, but some of the tracks cover over the notes.  Everything still plays, but I can't see the notes, which makes it slightly difficult to edit, lol.

If each track contains different parts of the kit, and therefore different notes on the piano grid on the left, then I can't understand how they can cover each other up if all dragged onto one track. Or am I misunderstanding?

Just lasso the stacked clips by dragging over with the right mouse button (this will select all the clips, not just the top one) and then right click and choose "bounce to clip." Hey presto, all clips merged into one.

Skyline_UK
If each track contains different parts of the kit, and therefore different notes on the piano grid on the left, then I can't understand how they can cover each other up if all dragged onto one track. Or am I misunderstanding?

 
It's true. For example, when I drag the hi-hat track into the kick track, all I see are the hi-hat notes on that track.  The kick notes still play, I just can't see them.

sharke
Just lasso the stacked clips by dragging over with the right mouse button (this will select all the clips, not just the top one) and then right click and choose "bounce to clip." Hey presto, all clips merged into one.

I tried that, didn't work.  But I was sure I'd done it that way a few weeks ago.

You could save those tracks as a type 0 MIDI file. That will merge them.

It certainly would!