In version 6.0 the data files were completed by some additional data, which means that the lists created in the older versions of the GROMA system are not compatible with the new files. If you choose, while opening a coordinate list or measurements list a file which was created in some of the previous version of the GROMA system, the program will notify you that the file must be converted to the new format. If you confirm that you agree with the conversion, the program will leave the original file as a backup and will create a file with the same name in the new format. This new file can't be open in the older versions of the GROMA system. The original file from the older version will be kept as a backup (.~cr, .~me).
If you want to open the file in the 6.0 format in some of the older versions, you must first export in the older format by the command File->Save as. In the format list, select Version 2-5. In this way, the created file can be opened without any problems in the older versions of the program. The new data types (date and time of the creation and modification of a report, additional point data, file comment, etc.) will be lost during the conversion into the older format.