One green bar of service?
which version of WinMX are you using? The last full GENUINE version of WinMX is 3.54 beta 4, there are other 'later' 'versions' but not genuine and not supported by their non-authorised authors. To get the proper winmx, go to http://patch.winmxconex.com
and download from there. Choose the Run option at the download prompt, and set a new folder (For example C:\Downloaded Music\), do NOT accept the default offered.
WinMX works fine with Windows 7 as long as you set folders other than the default for your downloads and your shares.
You may need to adjust port settings to get the full functions of WinMX but we can help you at any time, here i am 7,000km from home and still doing so
with my trusty lil netbook