It doesn't seem that SXI to DIF conversion is possible, because SXI is a presentation, whilst DIF is a very old spreadsheet format. Maybe some text data from the presentations could be imported to tables, but the conversion doesn't make sense at all.
This conversion entry was verified by us and conversion was flagged as wrong or not possible.
Usually this happens when the conversion would try to convert different types of data between each other, such as audio to image, or it is not possible because incompatibility between programs, caused by closed file formats, very limited support etc.
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