http://tech.groups.yahoo.com/group/yhoomediaplayer/ is the best place for this kind of help. Your questions here cover a lot of ground, definitely out of scope for the kind of tech support I do. When you post, it’s important to give the URL of your page, so that we can take a look at it.
Off the cuff answers:
#1: not showing tracks could mean something related to markup or something related to display. but you have much control over the playlist, yes… See http://yahoomediaplayer.wikia.com/wiki/How_to_link
#2: play button not showing is some conflict between your local CSS and the player’s. Definitely going to need to take out a debugger to solve it.
#3: HTML coding showing up in IE is completely no ok. that’s a live and high priority bug of some kind. but I’m sure there’s more to it than meets the eye.
you’re seeing a lot more problems than you should be. Not sure if it means that Y is completely abandoning the project or that your pages have a more complexity than ordinary, e.g. conflicting versions of YUI. Friends still at Yahoo tell me that it’s really not abandoned, fwiw.