1 - I don't know for sure but I think that display mode was replaced due to it being the least used. There was a poll several months ago asking people which display mode they used the most and that one turned out to be the least voted. I'm not sure if that's related though, just a guess.
3 - It might have something to do with the size and/or bitrate of your mp3. Try lowering the quality and see if that helps. I'm quite a bit out of date on the updates and improvements of multiMAN but there was a problem with larger mp3s at one point in time so it's worth a try.
Alternatively, try a different copy of the mp3. I've had issues in the past with some music downloaded from sites such as youtube that I was able to fix with a different copy of the song.
Hope that helps