Congratulations. Glad it worked for you.
Despite all the advice about popping caps before firing I have had guns that still had ignition problems. Even after several caps that would blow dirt there would still be a delay. This was after cleaning with brake cleaner, alcohol, solvents, detergents, etc.
As some did note, clean it out good.
I got a .32cal bore brush with a steel cleaning rod and chucked it in a slow speed drill. Put it in the chamber and ran it for a bit. Ran a patch in there to clean all the crud out and then did it again. Got more crud. One more time and it was clean.
Then the flash channel. Used a piece of wire that just barely fit. Filed a chisel end on it and ran it in and out of the flash channel until I got no more crud out of there. Then cleaned it.
I oil the gun with Remoil to prevent rust. Before shooting I pour some alcohol down the barrel and let it run out where the nipple seats.
When loading hold barrel with nipple low and tap the barrel so some powder will be in the flash channel. Like stated above, leave the hammer on half cock when loading so some of the powder can be 'blown' into the channel.
Like you found out, charging the flash channel after loading is a good method as well.