Just unzip them all and either rezip under normal compression or just import as mp3g.
From what I recall in the past most of these problems were because many/most/all of the files were zipped with an older version of mp3gtoolz. Max compression or not, Hoster (as well as Windows)did not like the way they were zipped.
It's my understanding that the newest version of toolz does not create these problems.
Sam
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