Oh, I see what's wrong.  It doesn't actually show the column as being
marked, and then, when I paste, it doesn't actually update the screen,
so it looks like nothing happened.  I have to leave the pattern and come
back to see that something was pasted.  Also, it doesn't seem to let me
copy one channel to another, or to paste it in some other place than the
beginning.

> Is that how it is in Protracker?  If so let me know and I'll add it.

I don't know how protracker works.  But every tracker since then uses i,
9, o, 0, and p.  I guess you're already using O and P, but there's no
reason not to use i and 9.