I played "Yellow Belly Beat" and this is what happened on my first attempt:

If you're interested, here's a bit of a review I have on your song:

The big thing I noticed about your file is that the BPM you chose is a weird ratio of the actual BPM.
I worked out the BPM for this song and in order to keep every step properly synched up to the music, the BPM should be 120 (or 240 if you wish to double it), not 175.
I'm not quite sure how you got 175. As far as I know, that isn't any musically-useful ratio of 120. 175 is 45.83% faster than 120. If that was, say, 33% faster I could see it making sense but I'm just not quite sure where the number 175 comes from.
If you made it faster just to make the arrows faster..my advice: don't do that

it knocks a lot of steps out of sync. That's what the 1.5x, 2x, etc. features are for. I was getting a lot of greats because I was trying to ignore the music and just hit the arrows because they were off-sync. If you reduce the BPM to 120 and change the blue (8th) notes to yellow (16th) notes (after making other necessary changes, of course), it will probably feel more in-sync.

I can prove to you that it's 120.000 BPM with this little audio file:
I set up a click track at 120 BPM, playing over top of the Yellow Belly Beat song. If you listen to this whole song, the click stays perfectly in sync with the music. that click is exactly 120 BPM the whole time.
Yellow Belly Beat with 120 BPM click trackI've made hundreds of Stepmania songs by now so if you have any questions, feel free to ask.
