Hopefully not the same things that plagued your previous utility. I would imagine you could approach it like CloneDVD does, where it only works on unencrypted DVDs. If a user wants to do something more than that, then there are those helper apps that take care of that issue. Also, making CD images should of course be for straight data type CDs, not protected games.
"approach it like CloneDVD does" - you mean like offer another product for sale that does the decrypting part?