As I know there is not any plans for Dsx support anymore. For migration between IS and CP4D you have to use ISX files. In CP4D itself JSON extracts are planned.
I agree that DSX is useful format for job manipulating (especially if you have some framework in your environment). ISX could be also modified externally. ISX is just zip file with xml files inside. XML are not similar to XML Designer output (which is DSX split into XML nodes) but more related to XMETA structure.
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Marcin Molak
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