I found a small problem that:
in the piano roll,I have set on [view---piano roll notes---show note names on notes] , meanwhile in reaper.ini [shownotenames=1], but next time when I restart reaper, [view---piano roll notes---show note names on notes] is still off. I tried it several times, and couldn't set on [view---piano roll notes---show note names on notes] as default.
file:reaper.ini
lastvelhand=1 ------Show velocity handles on notes
shownotenames=1 ---------show note names on notes
lastvelnum=1 ------Show velocity numbers on notes
only [shownotenames=1] has no effect.
This is a bug of reaper itself, I think.