File Format Version
When creating the export file, the format of the file is specific and the CMA import step knows how to read the file.  There are times when the product makes an enhancement to CMA that requires a change in the structure of the export file at which point the 'version' of the CMA file is incremented.
The CMA file format version has no impact to migrations that are exported and then imported into the same version of Oracle Utilities Application Framework. However, if your implementation has different environments on different versions of the product where the CMA file format is also different, then the system has functionality to cater for these differences.
If you are exporting data from a lower file format version to a higher file format version, there is nothing special that you need to do. The export step captures the file format version and the import step reads this information and processes the file accordingly.
If you are exporting data from a higher file format version to a lower file format version, you must indicate the desired target file format version when creating the migration data export.