Cracks you don't want. As indicated before, it is the %RH being too low. You can arrest this by waxing, the one thing is that if you get a void, mold could develop there. The outer layer that forms on the cheese is kind of like the curing barrier. In fact some cheeses, especially soft ripened cheese, will literally halt the maturation process once that barrier is broken. Now in the case of your Colby this is probably not as big a deal, but how deep are these cracks? I'd suggest waxing, trying to get the cracks filled first and then coating the whole thing.
Or, what may be best in this case is that if it has gone long enough, then to use it. That's probably how I'd do it actually. You would probably get unexpected results by trying to 'fix' this issue now so the product you have to this point might be better than if you were to try to continue the aging process post-waxing. But that is just a guess.