Well I have not used real black powder for a very long time but when I was a kid my dad always used to make me clean his after shooting with just plain old soap and hot water in the kitchen sink. After everything was cleaned up a light coat of oil was applied and we never had a problem. I had a chance to use and hunt with some tripple7 powder about 7 years ago in a muzzleloader and that stuff was great for cleaning. Again just a patch soaked with water and the gun would be clean after a few patches and never had any rust issues at all.
I have always just cleaned my black powder firearms in hot water and Pinesol. Both cap and ball revolvers, inlines, and traditional muzzle loaders. With the traditional I wipe it down with Thompson Center Bore Butter but for the others I just apply a little bit of oil and have never had a problem. Now when I say hot water I mean boiling hot water. It will get the metal so hot that you have a hard time holding onto it and once the metal is that hot any water that touches it will evaporate quite quickly.
Try to put your tree stand in a tree with plenty of background cover, keep the prevailing winds for that time of the year to your face, and take care of those pesky squeaks and creaks your stand may have developed while sitting in the shed. A good treestand lube can be made by heating petroleum jelly until it reaches a liquid form. Some hunters have reported success by including a cover scent in this mixture before applying it to their stands.