Well firstly, I appologise for the late reply, I have a terrible habbit of not reading my privatemsgs, here, however, the script runs fine here, using WinAmp version, 5.03 (should be fine on .04) make sure in the previous thread you did exactly what it said on how to register the dll, and it SHOULD have worked fine.
Also your missing a } at the end of the script after .comclose winamp. - My guess, a typo Edit
; Just downloaded 5.04, Works fine here, my guess is the dll isnt registered correctly, or isnt in the winamp plugin directory, or C:\program files\winamp isnt your default dir, if not, change the script line.
Recheck the Dll is registered with Windows, //comreg "C:\Program Files\Winamp\Plugins\gen_scripting.dll"
Change the above file location according to your Winamp install file.