Uwizard shouldn't know about Minecraft Story Mode, unless you have an updated gamedatabase.txt from somewhere, so it can't tell you on the main screen that the key is wrong. DiscU's output (after you click Extract Game Files) will tell you though.
Anyway, what Uwizard calls the title key is the wud key. Don't confuse that with the encrypted NUS key. For BAKE01, the wud key ends with the same byte (two hex chars) that the common key starts with. If you're using something else, it's not going to work.
Be sure that if you're importing the key from a 16 byte key file, you've renamed it with a .bin extension so Uwizard sees it and imports it properly.
Just to make sure it was working, I continued with extracting the files using uwizard without any problem. Of course, that gives you a loadiine format game, which isn't what this thread is about, but it shows that the key works.