Hey! I remember these games. I went through a huge In the Groove phase back in the day, followed by Stepmania when I got lazy and realized how much money I was spending in the arcades.
This is the Season 1 song pack. It isn't actually related to Friendship is Magic season one, in fact only a few of the songs are straight remixes.
I went through all of them on expert and was pleasently surprised. Usually SM packs are hit or miss, but all of these songs were well timed and the variety is great. Some are technical, others are speedy. Now I just need to buy a DDR pad for the computer...
Anyway, head on over to this page (see below if it wont work ) to download them. You will need a program to run it. Simply follow the instructions in the included readme.
Have a mirror if the link wont load.