Hmm... apparently there seem to be no differences, as I had a friend of mine test out this course on 4.0 with no problems. Odd, considering I remember that in 4.0 Mini is supposed to be Tiny or something to that degree. Must have changed in the current release...
And I am finishing up a course but lack a place to host it because it contains official songs.
Here's the course if you are interested at taking a peek.
Any chance of there being a course database here or somewhere soon so I can have someplace to host these courses I make, whether with official songs or original songs?