i fixed an early Couesnon (i believe it was) Eb, maybe it was a C, earlier this year or late last year.
The register vent height was very tricky. Too much or too little and things went whacko. I can't recall specifics though.
depending upon where cracks are and whether they are surface or all the way through ....
i normally oil up the instrument first to stabilize the wood - but you have to give it proper drying time after that for glue adhesion. Make it as it should just in case it is too shrunk. I've had to oil wood that was whitish in color, very shrunk but proper oiling brings it back to life and hopefully back to close to the original specifications (depending upon how dry it is).
now dealing with cracks is tricky.
I've developed a process, in certain situations, where I cool the instrument,
then warm the bore, which expands the instrument and shows the crack.
as shown here in pictures
http://clarinetperfection.com/WhyCrack.htm
then insert industrial super glue into the crack(s), and then cool the bore and all comes together.
but I also seal the location where the crack was (if not visible) as very minute fissures could exist which may still minutely affect the playability of the instrument - especially if the crack went through a tonehole. You could also use more superglue too just to be safe.
Ever hear someone say an instrument never played the same after a crack and crack fix ? It's usually because there is still some form of leak or, for lack of a good definition, "pressure fissure" where the air pressure from playing finds a small crack fissure and explores it. It's like having a cut pad. It seals, with problems.
The bell is a bit different.
The bell, just (after oiling if needed), superglue the outside and inside. I also always try to "blow" the glue into the crack. Or a thin piece of paper may work to work it in. It also depends upon how big the crack is if you need to fill it. But i use a really fine airstream (technique & pressure improved over time to prevent it from just blowing everywhere) on those super fine cracks.
i've found in cases that heat will give you a longer curing time and more time to get things right too.
then wipe away excess. cool, let harden, polish and make it look nice.