Must be something on your end. Works fine here
Code:
16:32:22 - Selected ARC/DS method for Data1a-01.bin was: xtool:mzlib:mreflate:dd3:l10,d128mb
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19:48:47 - Overall input size: 86.49 GB
19:48:47 - Overall output size: 60.39 GB (Ratio 69.82%)
19:48:47 - Overall conversion time: 03:16:23