Weird Seeding behaviour / n00b understanding

On another tracker I seed several torrents .. the weird thing, sometimes I run uploads with full 10 MBit (seedbox) and sometimes I have something like this :

http://i14.tinypic.com/4cw2wjr.jpg

What I don't understand is why it says it actually has peers but 0k upload rate ..

Also I don't get the why it says 0 peers but in (4) for example ...

btw. sometimes it says a higher ratio then the uploaded size in the above screenshot.. the reason is that some tracker need the stop message to update the ratio so I stop / start certain torrents every now and then ..