Just secondary with the maple and prime with regular dextrose.
Yes, you can prime with maple syrup. Dilute it with water, take the gravity, compare it to the gravity of the appropriate level of priming sugar dissolved in an equal amount of water, and go from there.
Of course, you may still have mixing problems... and the end result will be no better flavor-wise than if you had just chucked it into the secondary and let it do it's thing.
Priming with alternate substances works and is fine, but I can't for the life of me figure out why it would ever be any better than adding the same substance in secondary... I've primed with honey and extract, and a few other things. I think it's all a waste of time. I add that stuff to secondary now.
The only 2 reasons to prime with something else that make any sense to me are either so you can say your beer complies with Reinheitsgebot or so that you can say, "bottle conditioned with (whatever substance)". Other than that, I don't really see the point, I don't think it does more for the taste than just adding it to secondary.
