At 225° it probably just needs more time, that is a pretty low temp, for a big baker potato I'm guessing you would need more like 4 hrs. You can also zap them in the microwave for 5-10 min. at the very end if they aren't quite cooked through, they will still come out very tastey.
If you haven't tried it yet I highly recomend twice "smoked" potatos! Smoke them till tender, cut a wedge out of the top and scoop out the insides. Mix the insides with sharp chedder, green onions, sour cream, salt, pepper, and a little butter, spoon that all back into the taters and then smoke them again for another 1-2 hrs. They are sooooo goooood!