I use Pyrodex P in all my BPs. Now some won't agree with this but to each their own. Was using RS in rifles using #11 primers but experienced too many hesitations. RS works fine in my inline with 209 primer. FF is too coarse for pistol. Not that it won't pop but the burn rate not suited for them. I have the same pistol. I also have a formula I reverse worked from an article about find peak efficient load. It does not give the exact load but rather gives a good safe starting point using round ball.
Bore radius squared x 3.1416 x barrel lemgth x 15.72
For this pistol, if I got barrel length right, comes to 13.77. So a good start point is 14grains. Every gun shoots different so adjust from there. In mine I don't go past 25 grains, even in the 7.5 barrel. With conicals I drop powder 10%.
There are all kinds of lube out there you can use to seal the cylinder with. I've been using wax melted together with veg oil for years. Inexpensive to make and easy. I use it for patch lube too. Make some to a consistency it can be used in bakers syringe for revolver cylinder.
Another thing you might check is that the cylinder bore provides projectile diameter fits barrel max diameter. Sometimes, for what ever reason, this happens. I just picked up a colt walker and found the cylinder bore was delivering a projectile that was 0.005 less than the max 0.44 barrel bore. Meaning it was barley catching riflings and leaving gap to barrel max. It is something to look into if the accuracy is an issue for you. Some take to gun smith to rebore cylinder. I lucked out and was close and able to hone polish to good diameter.
Always use projectile that when pressed into cylinder cuts a ring of lead to insure tight seal. If you mold your own only use pure lead.
#10 primers.
Lots of ways to clean. I take grips off and use hot soapy water. Soak about 10 minutes then brush and mop. Rinse with very hot water. The residual heat helps it dry quickly. Drop or two of oil on all moving parts. Light oil mop cylinder bore and barrel mainly for preservation durring storage. Clean out oil before next shoot. Then I go over outside with silicone cloth.
What I do. Everybody has their on ideas.