Oops, just discovered that the address of the OrangeWire you posted falls into a blocked range on the LW Security Blocklist.
Your listing does not show their port number, but it is my guess they use port 7001. Check this page http://www.gnutellaforums.com/open-d...imewire-7.html about half way down, the first black ip addresses you see where I found them via Phex. 66.212.143.104:7001 through to 66.212.143.116:7001
And the one shown uploading from you was 66.212.143.109
All belong to BMI (Broadcast Music, Inc.) and are known for upload slot containment (ie: will try to fill your upload slots & keep them busy, usually going after your largest files or largest collection of files. These are Download-Bots.) Here's my upload window from BearShare Click to see BearShare Upload window. Whilst using Phex I also had problems with same hosts since a year earlier filling my upload slots.

In retrospect, I have doubts the WinMX Music versions you were seeing are official WinMX Music versions but adapted by the anti-file-sharing company to behave like they do (BOTs). Your uploads might not have had more of them because your uploads are super busy anyway & they struggled to get a slot.
I've heard Vista firewall is same as Win XP firewall. If using Win 7 or later, the firewall has the ability to block ports such as 7001 and 27016 and can be set to be only active when using particular programs. (Port forwarding sometimes breaks/by-passes this firewall port block however!)

The security blocklist has ip ranges blocked from 66.211.128.0 through to 66.213.191.255 (these are corporate business ranges, mostly in the entertainment industry.) If you think that's too heavy, you could either use 66.212.0.0/16 or 66.212.143.0/24 if you wish to block them. The port 7001 bots are not spammers AFAIK, their objective is to fill your upload-slots in an attempt to prevent you sharing certain files to others.