Speaking of changing the rules for hunting... I wish I could hunt with my muzzle loader during modern firearm season too. .
You most certainly can hunt with your MZ during the modern rifle season. You can have both of them with you in the blind during modern rifle season. You can't have a modern rifle with you during MZ season though.
For the hang fires, etc, make sure you have a nipple pick to clean out the passage and fire a few caps before loading to clear any residual oil, etc from the nipple/chamber.