There is no built-in mechanism in Kmax for writing zero-suppressed event files. Over the years we have discussed doing this and continue to consider the options. Unfortunately, there is no format for zero-suppressed data in common use. The structure of headers and the size of tag and data words are the most common differences. Several module venders have implemented zero-suppression in hardware, but different formats have been used. If you save the Event Buffers with zeros suppressed, you will need to read and analyze the files manually.  This can be done using the Kmax FILE variable type.