Upload speed

I really have no bad news to report. Isn't that nice!
Limewire is working exceptionally well. I got my firewall problem straightened out and Limewire and iTunes work well together.
A couple of questions though. I have been designated a Limewire Ultrapeer. I've noticed some uploads are slow as death even though I have a cable connection. Other uploads, sometimes at the same time are fast as lightening. Anyone got any ideas why this is?
The other question has to do with my ipod. I downloaded an entire album and it plays fine in iTunes. I transferred it to my ipod but it won't play. Why???
I'm curious more than anything.
All the best
itsbkn