Regarding Mr. Saint-Dennis's primary valve problem:  I had the same
problem with an Otto Higel double-valve wooden player action.  After I
replaced the zephir skin with ordinary tan pouch leather, I experienced
some laziness and some reluctance in the opening of the valves.

I replaced the pouches again, but this time with the thinnest pouch
leather I have.  Usually I make the depression in the pouch before
I glue it into the pouch hole.  This time I glued the pouch without
making the depression, and after the glue dried I stretched the pouch
leather with a round marble, big enough just to enter a small part of
it, so all the 88 pouches took the same size.

After this I sealed them with what in my country we call "Holland
grease", or "Barbour cloth grease".  It's a grease that protects cloth
and leather material from rain -- the leather stays air-tight and (what
you most want) flexible.  If your pouch action uses a disk lifter you
just can't use this grease, because nothing glues on this.

All these tips came from an old Portuguese organ rebuilder, and with
the help of all of you, of course.

Finally the result: just superb, one of the most responsive actions
I ever restored!

Good luck with your work

Miguel de Mattos
Lisbon, Portugal