Oh man, it's been a while since I've deciphered hit object code.
That means you placed a slider, and it has a set of anchor points that has to be stored in the line (B|384:176|480:152, I'm guessing, although the format seems to have changed). The 2,2, before that indicates it's a slider, and which hitsound it's using, and the first two numbers are the starting coordinates of the slider. I don't know what the rest of the stuff after the anchor point information means.
I may be wrong, because sliders are confusing, and the code looks quite different from the ones I used to deal with.