Ronbow, I clean the nipples on the outside with soapy water and a toothbrush. I blow my cylinders dry and take extra care to blast the nipples well. I have an air compressor, but before I did I had a tire inflator. Cost me about $20 and it came with a small nozzle too. I use a small tipped air gun now. I think I got the tire inflator at Kragens/Shucks auto parts store. 110v and it runs continually. I do not use a pick at all. The last thing I want is bigger holes, that causes caps to blow off and gum up the works.
I have a way of cleaning nipples on the outside while at a shoot. I have a small piece of synflex (plastic tubing) that fits right onto my nipples. I happened to have a 6 pointed cutter that is very sharp that came with my dremel. I put the tubing in the vise and force the small cutter into the tubing. I now have a tube with little flaps on the inside. I will run that over my nipples after about 3 stages ( 15 rounds each pistol, for non CAS shooters). This helps me fully seat my caps onto my Treso nipples with only my Ted Cash double fingered stick capper.
I can't afford to go around a second time if all the first hit did was seat the cap. I demand the same reliable boom, clang that cartridge shooters do.
Along the same lines, I keep a silicone sprayed 10 gauge bore mop in a plastic sleeve and I run that up and out of my SxS chambers after 3 stages also. That keeps my empty hulls flying out with a flip of the wrist upon firing.
I shot a pair of 8" barreled ROAs two matches this past weekend and I had not shot them since moving ( before January ) I did nothing to them other than switch grips when I dug them out from in back of the safe. I am used to gunfighter grips, but am too cheap to outfit all my ROAs with them.
I hope this helps. Remember the neversieze. Good clean and dry threads, a thin coat of neversieze ( available at auto parts stores in small tubes ) and tighten down flat.
When setting up C&Bs, I like to measure the cylinder and nipples together. That way each is at the same height. Uberti and Piettas vary and sometimes thin shim washers are needed for all to be exactly at the same height. I have not had to shim an ROA though, but I have had to file a couple standard Ruger stainless nipples that were too long. I measure with a digital verneer caliper.
To make a C&B sing it does take some initial setting up, but it is well worth it in the end.
:-)