I don't really see how the following may have set up a barrier of sorts but try them out anyway (you never know):

-try having only one dld to see if it will progress further than 20508K

-go to Options/Preferences and take a look at how the following categories are configured: Downloads, Uploads->Basic, Uploads->Slots. Post back the results along with your connection speeds (download and upload)

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iMac G4 OSX 10.3.9
RAM 256MB
LW 4.10.5 Basic
ADSL anything from 3 to 8Mbps/around 1024kbps

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And seal your fate forever
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The Golden Age Of Leather"
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