Chances are that it's just people uploading a file from you, disconnecting the download (or getting disconnected) & then continuing the download again. Are you firewalled? Were you firewalled when using LW 4? Has there been any change in your setup, apart from updating LW?

Each version of LW behaves differently & LW 5 is very different to LW 4... maybe upload behaviour has changed in the new version? I've seen the same kind of thing in Windows, though not to the same degree that you've mentioned.

You could ask over at the developers' forum - one of the devs might be able to explain more.
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